Journal articles on the topic 'Random effect negative binomial models (RENB)'
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Shankar, Venkataraman N., Richard B. Albin, John C. Milton, and Fred L. Mannering. "Evaluating Median Crossover Likelihoods with Clustered Accident Counts: An Empirical Inquiry Using the Random Effects Negative Binomial Model." Transportation Research Record: Journal of the Transportation Research Board 1635, no. 1 (January 1998): 44–48. http://dx.doi.org/10.3141/1635-06.
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Insights into plausible methodological frameworks specifically with respect to two key issues—(1) mathematical formulation of the underlying process affecting median crossover accidents and (2) the factors affecting median crossover frequencies in Washington State—are provided in this study. Random effects negative binomial (RENB) and the cross-sectional negative binomial (NB) models are examined. The specification comparisons indicate benefits from using the RENB model only when spatial and temporal effects are totally unobserved. When spatial and temporal effects are explicitly included, the NB model is statistically adequate, while the RENB model appears to lose its distributional advantage. Such findings might be artifacts of the median crossover accident dataset used in this study. While the NB model appears to be the superior model in the present case of median crossover accidents, the marginally inferior performance of the RENB model warrants further examination through application to regular accident types in light of its flexibility to incorporate temporal and cross-sectional variations simultaneously in panel counts. From a predictive standpoint, RENB offers advantages in terms of model transferability and updating.
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Tulu, Getu Segni, M. Mazharul Haque, Simon Washington, and Mark J. King. "Investigating Pedestrian Injury Crashes on Modern Roundabouts in Addis Ababa, Ethiopia." Transportation Research Record: Journal of the Transportation Research Board 2512, no. 1 (January 2015): 1–10. http://dx.doi.org/10.3141/2512-01.
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Pedestrian crashes represent about 40% of total fatal crashes in low-income developing countries. Although many pedestrian crashes in these countries occur at unsignalized intersections such as roundabouts, studies focusing on this issue are limited. The objective of this study was to develop safety performance functions for pedestrian crashes at modern roundabouts to identify significant roadway geometric, traffic, and land use characteristics related to pedestrian safety. Detailed data, including various forms of exposure, geometric and traffic characteristics, and spatial factors such as proximity to schools and to drinking establishments were collected from a sample of 22 modern roundabouts in Addis Ababa, Ethiopia, representing about 56% of such roundabouts in Addis Ababa. To account for spatial correlation resulting from multiple observations at a roundabout, both the random effect Poisson (REP) and random effect negative binomial (RENB) regression models were estimated. Model goodness-of-fit statistics revealed a marginally superior fit of the REP model to the data compared with the RENB model. Pedestrian crossing volume and the product of traffic volumes along major and minor roads had significant and positive associations with pedestrian crashes at roundabouts. The presence of a public transport (bus or taxi) terminal beside a roundabout was associated with increased pedestrian crashes. Although the maximum gradient of an approach road was negatively associated with pedestrian safety, the provision of a raised median along an approach appeared to increase pedestrian safety at roundabouts. Remedial measures were identified for combating pedestrian safety problems at roundabouts in the context of a developing country.
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Noh, Maengseok, and Youngjo Lee. "Extended negative binomial hurdle models." Statistical Methods in Medical Research 28, no. 5 (April 11, 2018): 1540–51. http://dx.doi.org/10.1177/0962280218766567.
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Poisson models are widely used for statistical inference on count data. However, zero-inflation or zero-deflation with either overdispersion or underdispersion could occur. Currently, there is no available model for count data, that allows excessive occurrence of zeros along with underdispersion in non-zero counts, even though there have been reported necessity of such models. Furthermore, given an excessive zero rate, we need a model that allows a larger degree of overdispersion than existing models. In this paper, we use a random-effect model to produce a general statistical model for accommodating such phenomenon occurring in real data analyses.
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Mićić, Spasoje, Radoje Vujadinović, Goran Amidžić, Milanko Damjanović, and Boško Matović. "Accident Frequency Prediction Model for Flat Rural Roads in Serbia." Sustainability 14, no. 13 (June 24, 2022): 7704. http://dx.doi.org/10.3390/su14137704.
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Traffic accidents, by their nature, are random events; therefore, it is difficult to estimate the exact places and times of their occurrences and the true nature of their impacts. Although they are hard to precisely predict, preventative actions can be taken and their numbers (in a certain period) can be approximately predicted. In this study, we investigated the relationship between accident frequency and factors that affect accident frequency; we used accident data for events that occurred on a flat rural state road in Serbia. The analysis was conducted using five statistical models, i.e., Poisson, negative binomial, random effect negative binomial, zero-inflated Poisson, and zero-inflated negative binomial models. The results indicated that the random effect negative binomial model outperformed the other models in terms of goodness-of-fit measures; it was chosen as the accident prediction model for flat rural roads. Four explanatory variables—annual average daily traffic, segment length, number of horizontal curves, and access road density—were found to significantly affect accident frequency. The results of this research can help road authorities make decisions about interventions and investments in road networks, designing new roads, and reconstructing existing roads.
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Bae, Bumjoon, Changju Lee, Tae-Young Pak, and Sunghoon Lee. "Identifying Temporal Aggregation Effect on Crash-Frequency Modeling." Sustainability 13, no. 11 (May 31, 2021): 6214. http://dx.doi.org/10.3390/su13116214.
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Aggregation of spatiotemporal data can encounter potential information loss or distort attributes via individual observation, which would influence modeling results and lead to an erroneous inference, named the ecological fallacy. Therefore, deciding spatial and temporal resolution is a fundamental consideration in a spatiotemporal analysis. The modifiable temporal unit problem (MTUP) occurs when using data that is temporally aggregated. While consideration of the spatial dimension has been increasingly studied, the counterpart, a temporal unit, is rarely considered, particularly in the traffic safety modeling field. The purpose of this research is to identify the MTUP effect in crash-frequency modeling using data with various temporal scales. A sensitivity analysis framework is adopted with four negative binomial regression models and four random effect negative binomial models having yearly, quarterly, monthly, and weekly temporal units. As the different temporal unit was applied, the result of the model estimation also changed in terms of the mean and significance of the parameter estimates. Increasing temporal correlation due to using the small temporal unit can be handled with the random effect models.
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Zhu, Huirong, Sheng Luo, and Stacia M. DeSantis. "Zero-inflated count models for longitudinal measurements with heterogeneous random effects." Statistical Methods in Medical Research 26, no. 4 (June 24, 2015): 1774–86. http://dx.doi.org/10.1177/0962280215588224.
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Longitudinal zero-inflated count data arise frequently in substance use research when assessing the effects of behavioral and pharmacological interventions. Zero-inflated count models (e.g. zero-inflated Poisson or zero-inflated negative binomial) with random effects have been developed to analyze this type of data. In random effects zero-inflated count models, the random effects covariance matrix is typically assumed to be homogeneous (constant across subjects). However, in many situations this matrix may be heterogeneous (differ by measured covariates). In this paper, we extend zero-inflated count models to account for random effects heterogeneity by modeling their variance as a function of covariates. We show via simulation that ignoring intervention and covariate-specific heterogeneity can produce biased estimates of covariate and random effect estimates. Moreover, those biased estimates can be rectified by correctly modeling the random effects covariance structure. The methodological development is motivated by and applied to the Combined Pharmacotherapies and Behavioral Interventions for Alcohol Dependence (COMBINE) study, the largest clinical trial of alcohol dependence performed in United States with 1383 individuals.
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Stapleton, Steven Y., Timothy J. Gates, Raul Avelar, Srinivas R. Geedipally, and Ramin Saedi. "Safety Performance Functions for Low-Volume Rural Stop-Controlled Intersections." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 5 (April 12, 2019): 660–69. http://dx.doi.org/10.1177/0361198119840348.
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This study involved the development of safety performance functions for rural, low-volume, minor road stop-controlled intersections in Michigan. Facility types included three-leg stop-controlled (3ST) and four-leg stop-controlled (4ST) intersections under state or county jurisdiction and were sampled from each of Michigan’s 83 counties. To isolate lower-volume rural intersections, major roadway traffic volumes were limited to the range of 400–2,000 vehicles per day (vpd). Data were compiled from several sources for 2,023 intersections statewide. These data included traffic crashes, volumes, roadway classification, geometry, cross-sectional features, and other site characteristics covering the period of 2011–2015. Random effects negative binomial regression models were specified for each stop-controlled intersection type considering factors such as driveway density, lighting presence, turn lane presence, and intersection skew, in addition to volume. To account for the unobserved heterogeneity between counties, mixed effects negative binomial models with a county-specific random effect were utilized. Furthermore, unobserved temporal effects were controlled through the use of a year-specific random effect. Separate models were developed for fatal/injury crashes, property damage crashes, and select target crash types. The analysis found that skew angles of greater than five degrees led to significantly greater crash occurrence for both 3ST and 4ST intersections, while greater than two driveways near the intersection led to significantly greater angle crashes at 4ST intersections. Other factors were found to have little impact on crash occurrence. Comparison with the Highway Safety Manual (HSM) base models showed that the HSM models over-predict crashes on 4ST intersections and 3ST intersections with volumes between 1,200 and 2,000 vpd.
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Woolliams, J. A., Z. W. Luo, B. Villanueva, D. Waddington, P. J. Broadbent, W. A. C. McKelvey, and J. J. Robinson. "Analysis of factors affecting superovulatory responses in ruminants." Journal of Agricultural Science 124, no. 1 (February 1995): 61–70. http://dx.doi.org/10.1017/s0021859600071252.
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SUMMARYData on ovulation rate and numbers of ova and transferable embryos recovered from superovulated cattle and sheep were analysed using generalized linear models, quasi-likelihood, restricted maximum likelihood (REML) and generalized linear mixed models (GLMMS). The data pertained to the operation of nucleus breeding schemes in cattle and the commercial application of embryo transfer in sheep.Results of the analyses showed that generalized linear models involving Poisson and Binomial distributions were inappropriate because of over-dispersion, and that analyses using quasi-likelihood to model negative binomial and β-binomial distributions were more suitable. Factors identified as important in determining the results in cattle were the number of previous superovulations (a higher proportion of transferable embryos were obtained in the initial flush compared to subsequent recoveries in two out of three sets of data), the donor (significant in all analyses with repeated recoveries) and its mate (significant in some analyses). In sheep, the use of pFSH or hMG for superovulation increased embryo yields above those obtained with PMSG + GnRH. Analyses of a further data set for sheep showed the effect of breed was ambiguous.The effects of donors and their mates were treated as random effects in analyses involving REML and GLMMS. Results showed that the repeatability of the number of transferable embryos produced per donor ranged between 0·13 and 0·23 in three sets of data and was significant in all cases. In these analyses the variance among mates was not significantly different from zero.The results of analyses were used to develop a random generator to simulate the numbers of ova and embryos recovered from a cow following superovulation. By sampling from negative binomial distributions where the scale factor used for each cow was a normally distributed deviate, distributions were obtained which had the same mean, variance and repeatability as those observed.
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Champahom, Thanapong, Sajjakaj Jomnonkwao, Chinnakrit Banyong, Watanya Nambulee, Ampol Karoonsoontawong, and Vatanavongs Ratanavaraha. "Analysis of Crash Frequency and Crash Severity in Thailand: Hierarchical Structure Models Approach." Sustainability 13, no. 18 (September 9, 2021): 10086. http://dx.doi.org/10.3390/su131810086.
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Currently, research on the development of crash models in terms of crash frequency on road segments and crash severity applies the principles of spatial analysis and heterogeneity due to the methods’ suitability compared with traditional models. This study focuses on crash severity and frequency in Thailand. Moreover, this study aims to understand crash frequency and fatality. The result of the intra-class correlation coefficient found that the spatial approach should analyze the data. The crash frequency model’s best fit is a spatial zero-inflated negative binomial model (SZINB). The results of the random parameters of SZINB are insignificant, except for the intercept. The crash frequency model’s significant variables include the length of the segment and average annual traffic volume for the fixed parameters. Conversely, the study finds that the best fit model of crash severity is a logistic regression with spatial correlations. The variances of random effect are significant such as the intersection, sideswipe crash, and head-on crash. Meanwhile, the fixed-effect variables significant to fatality risk include motorcycles, gender, non-use of safety equipment, and nighttime collision. The paper proposes a policy applicable to agencies responsible for driver training, law enforcement, and those involved in crash-reduction campaigns.
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Rohmaniah, Siti Alfiatur, and Novita Eka Chandra. "PERHITUNGAN PREMI ASURANSI JIWA MENGGUNAKAN GENERALIZED LINEAR MIXED MODELS." Jurnal Ilmiah Teknosains 4, no. 2 (January 3, 2019): 80. http://dx.doi.org/10.26877/jitek.v4i2.3004.
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The price of life insurance premiums for each person depends on the probability of death, not only based on age and gender as offered by an Indonesian insurance company. The purpose of this study is to determine premium prices on underwriting factors and frailty factors using Generalized Linear Mixed Models (GLMM). GLMM is used for modeling a combination of fixed effect heterogeneity (underwriting factors) and random effects (frailty factors) between individuals. The data used longitudinal data about underwriting factors that have Binomial distribution are taken from the Health and Retirement Study and processed using R software. Because the data used by survey data within an interval of two years, so the probability of death is obtained for an interval the next two years. Underwriting factors that have a significant effect on the probability of death are age, alcoholic status, heart disease, and diabetes. As a result, is obtained the probability of death models each individual to determine life insurance premium prices. The premium price of each individual is different because depends on underwriting factors and frailty. If frailty is positive, it means that a person level of vulnerability when experiencing the risk of death is greater than negative frailty.
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Kuptsevych-Timmer, Anastasiia, Olena Antonaccio, Ekaterina V. Botchkovar, and William R. Smith. "Scared or Attached? Unraveling Important Links in Strain–Crime Relationships Among School Students." International Journal of Offender Therapy and Comparative Criminology 63, no. 8 (December 5, 2018): 1175–201. http://dx.doi.org/10.1177/0306624x18814342.
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Drawing on general strain theory of crime, the study employs the survey data from a random sample of 600 school students in Lviv, Ukraine, to examine how sanction risks and social bonds mediate and moderate the relationship between strain and adolescent delinquency. Findings from negative binomial regressions and the KHB decomposition procedure demonstrate that fear of sanctions and levels of social control mediate the relationships between strain and delinquency to a different degree, depending on the type of strain experienced. Results concerning conditioning effects are mixed, with only parental monitoring found to be a moderator of the strain–delinquency link. However, the direction of the interaction effect is unexpected. Future research needs to improve the specification of strain models and evaluate them in other sociocultural contexts.
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Rausch, Michael, Peter C. Boxall, and Arunas P. Verbyla. "The development of fire-induced damage functions for forest recreation activity in Alberta, Canada." International Journal of Wildland Fire 19, no. 1 (2010): 63. http://dx.doi.org/10.1071/wf08137.
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This study develops an intertemporal fire damage function for forest recreation activity in the eastern slopes region of the Canadian Rocky Mountains. The methodology employed combined revealed-stated preference data in which the behavioral response variable was annual camping trip frequencies. Photographs were used to portray changes in stand ages and related changes in trip frequencies. The data were analysed using negative binomial count data models. Unlike previous studies employing similar methods, a random effects specification was used to develop trip demand parameters. The results suggest that fires initially decrease annual trips from ~2.56 to 1.0 after the burn. As the stand ages, the effect of the fire decreases until ~12 years after the fire when the trip frequencies recover to about their previous ‘old-growth’ levels. This function is different from others described in the literature for similar mountain ecosystems in North America.
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GURJOT KAUR, PREETINDER SINGH SARAO, and PRITPAL SINGH. "Effect of weather variabilities on dispersion pattern of Nilaparvata lugens (Stål) (Homoptera: Delphacidae) in paddy field." Journal of Agrometeorology 24, no. 4 (December 2, 2022): 403–8. http://dx.doi.org/10.54386/jam.v24i4.1726.
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Field experiments were conducted to find out the impact of weather factors and crop phenological stages on the dispersion pattern of brown planthopper (BPH), Nilaparvata lugens (Stål) in paddy during kharif 2019 and 2020 at three paddy crop phenological stages like the active tillering stage (IV week of July to III week of August), panicle bearing and grain filling stage (IV week of August to III week of October) and grain maturity stage (IV week of October to IV week of November). Weather factors in relation with mean BPH population were subjected to multiple regression and correlation analysis. The dispersion patterns were studied by regression models using Index of dispersion, Elliott’s law, Taylor’s Power Law and Iwao’s patchiness regression model. Maximum population of BPH was observed during panicle bearing and grain filling stage at 108 days after transplanting. The BPH counts were fitted to negative binomial which indicated aggregated distribution in the field and most of the weather parameters like temperature, evening relative humidity and wind speed is negatively correlated during this stage. During active tillering and grain maturity stage, Poisson distribution pattern of BPH population in the field was observed which showed random distribution.
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SANDBERG, MARIANNE, MERETE HOFSHAGEN, ØYVIN ØSTENSVIK, EYSTEIN SKJERVE, and GILES INNOCENT. "Survival of Campylobacter on Frozen Broiler Carcasses as a Function of Time." Journal of Food Protection 68, no. 8 (August 1, 2005): 1600–1605. http://dx.doi.org/10.4315/0362-028x-68.8.1600.
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In the Norwegian Action Plan against Campylobacter in broilers, carcasses from flocks identified as positive before slaughter are either heat treated or frozen for 5 weeks to reduce the number of Campylobacter. The objective of this study was to estimate the effect of freezing time and predict the number of Campylobacter on naturally infected or contaminated broiler carcasses following freezing for 2, 4, 6, 8, 10, 13, 21, 35, and 120 days by nonparametric and parametric linear statistical models. From each of the five flocks, 27 carcasses were sampled. Each carcass was cut in two pieces along the chest bone. Half was put into the freezer (−20°C), whereas the other was deskinned and quantitative culturing was conducted from a 10-g sample of the skin. Fifteen frozen halves were selected at random at each time point following freezing from 2 to 120 days, and skin samples from these were cultured quantitatively and qualitatively. In regard to the log reduction of Campylobacter, almost similar results were obtained using three statistical methods; median regression on the change in Campylobacter counts, zero-inflated negative binomial regression, and a Bayesian Markov chain Monte Carlo (decay) model on original counts. Overall, a 2-log reduction of Campylobacter was obtained after 3 weeks of freezing. Only a marginal extra effect was observed when extending the freezing to 5 weeks. Although freezing appears to be an efficient way to reduce the level of Campylobacter on broiler carcasses, in 80% of the carcasses Campylobacter could still be detected using quantitative culturing following 120 days of freezing. Based on the high number of zeros, these data should be modeled by a zero-inflated model. The best statistical fit in regard to goodness-of-fit measures was the zero-inflated negative binomial log link model, closely followed by the Poisson model. Thus, in our continued search for a better way to describe the data, we used the Poisson distribution in the mixed Bayesian decay models.
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Wang, Erda, Jianhua Wei, and Jiawei Zhu. "The effects of improving coastal park attributes on the recreation demand—A case study in Dalian China." Tourism Economics 23, no. 1 (September 21, 2016): 133–49. http://dx.doi.org/10.5367/te.2015.0503.
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In this study, we use an estimation method of combining revealed preference (RP) with stated preference (SP) to measure the effects of park attribute improvement on the tourism demand and recreation benefits. Three categories of attributes are taken into account including nature, management, and economics. Five model estimations are made using RP, SP, and pooled data, respectively. The random effects negative binomial model is used with the SP data, and the mixed negative binomial model is used with the pooled data. The economic value of each specific park attribute improvement is measured by visitors’ marginal willingness to pay that directly addresses the issues of optimal attribute combinations beyond the observed range and scenarios. We survey a sample of the participants on the sites to obtain both revealed and stated behavior data for trips based on a management-relevant park attribute improvement and different park attribute combinations. Recreation demand models are used to derive total consumer surplus. The results indicate that the congestion reduction in the park has a relatively weak effect on the tourist demand, whereas trash reduction and improved seawater visibility appear to have the most important value to the tourists. Furthermore, the estimated consumer surplus at the present park conditions is about US$85 per recreation trip, and this consumer surplus will increase to US$101 as the quality of the park attribute improved. The overall park attribute improvement will increase recreational trip by 1.22 times per person per year from the present condition, and the net increase in consumer surplus reaches to US$205 per participant per year as a result of overall park attribute improvement.
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Guo, Rui, Zhiqiang Wu, Yu Zhang, Pei-Sung Lin, and Zhenyu Wang. "Insights from Integrated Geo-Location Data for Pedestrian Crashes, Demographics, and Land Uses." Transportation Research Record: Journal of the Transportation Research Board 2674, no. 8 (May 31, 2020): 720–31. http://dx.doi.org/10.1177/0361198120920267.
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This study investigates the effects of demographics and land uses on pedestrian crash frequency by integrating the contextual geo-location data. To address the issue of heterogeneity, three negative binomial models (with fixed parameters, with observed heterogeneity, and with both observed and unobserved heterogeneities) were examined. The best fit with the data was obtained by explicitly incorporating the observed and unobserved heterogeneity into the model. This highlights the need to accommodate both observed heterogeneity across neighborhood characteristics and unobserved heterogeneity in pedestrian crash frequency modeling. The marginal effect results imply that some land-use types (e.g., discount department stores and fast-food restaurants) could be candidate locations for the education campaigns to improve pedestrian safety. The observed heterogeneity of the area indicator suggests that priority should be given to more populated low-income areas for pedestrian safety, but attention is also needed for the higher-income areas with larger densities of bus stops and hotels. Moreover, three normally distributed random parameters (proportion of older adults, proportion of lower-speed roads, and density of convenience stores in the area) were identified as having random effects on the probability of pedestrian crash occurrences. Finally, the identification of pedestrian crash hot zone provides practitioners with prioritized neighborhoods (e.g., a list of areas) for developing effective pedestrian safety countermeasures.
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Geedipally, Srinivas R., Timothy J. Gates, Steven Stapleton, Anthony Ingle, and Raul E. Avelar. "Examining the Safety Performance and Injury Severity Characteristics of Rural County Roadways." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 10 (May 20, 2019): 405–15. http://dx.doi.org/10.1177/0361198119850127.
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Much of the earlier work on rural safety focused on state-maintained roadways and little is known about the safety performance of low-volume county-maintained roads. This study involved the estimation of safety performance for rural county roadways (paved and gravel). This was accomplished through the development of safety performance functions (SPFs) to estimate the number of annual crashes at a given highway segment, crash modification factors to determine the impacts associated with various roadway and geometric characteristics, and severity distribution functions (SDFs) to predict the crash severity. County road segment data were collected across a sample of 30 counties representing all regions of Michigan. Because of the overwhelming proportion of deer crashes, only non-deer-related crashes were considered. To minimize the influence of variability among counties, the random effect negative binomial model was used to develop SPFs. In addition, a multinomial logit model was used to develop SDFs. Paved county roadways showed approximately double the crash occurrence rate of typical state-maintained two-lane rural highways, and gravel roadways showed a substantially greater crash occurrence rate than paved county roadways across the equivalent range of traffic volumes. The economic analysis showed that it is beneficial to pave a gravel road when the traffic volume is greater than 600 vehicles per day. The random effect variable is significant in all the calibrated models, which shows that there is a considerable variability among counties that cannot be captured with the available variables. Not considering the random effects will result in biased estimation of crashes.
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Lobo, António, Sara Ferreira, Isabel Iglesias, and António Couto. "Urban Road Crashes and Weather Conditions: Untangling the Effects." Sustainability 11, no. 11 (June 6, 2019): 3176. http://dx.doi.org/10.3390/su11113176.
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Most previous studies show that inclement weather increases the risk of road users being involved in a traffic crash. However, some authors have demonstrated a little or even an opposite effect, observed both on crash frequency and severity. In urban roads, where a greater number of conflict points and heavier traffic represent a higher exposure to risk, the potential increase of crash risk caused by adverse weather deserves a special attention. This study investigates the impact of meteorological conditions on the frequency of road crashes in urban environment, using the city of Porto, Portugal as a case study. The weather effects were analyzed for different types of crashes: single-vehicle, multi-vehicle, property-damage-only, and injury crashes. The methodology is based on negative binomial and Poisson models with random parameters, considering the influence of daily precipitation and mean temperature, as well as the lagged effects of the precipitation accumulated during the previous month. The results show that rainy days are more prone to the occurrence of road crashes, although the past precipitation may attenuate such effect. Temperatures below 10 °C are associated with higher crash frequencies, complying with the impacts of precipitation in the context of the Portuguese climate characteristics.
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Sánchez-Sánchez, Rafael, Ignacio Reinal, Esteban Peiró-Molina, Marc Buigues, Sandra Tejedor, Amparo Hernándiz, Marta Selva, et al. "MicroRNA-4732-3p Is Dysregulated in Breast Cancer Patients with Cardiotoxicity, and Its Therapeutic Delivery Protects the Heart from Doxorubicin-Induced Oxidative Stress in Rats." Antioxidants 11, no. 10 (September 30, 2022): 1955. http://dx.doi.org/10.3390/antiox11101955.
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Anthracycline-induced cardiotoxicity is the most severe collateral effect of chemotherapy originated by an excess of oxidative stress in cardiomyocytes that leads to cardiac dysfunction. We assessed clinical data from patients with breast cancer receiving anthracyclines and searched for discriminating microRNAs between patients that developed cardiotoxicity (cases) and those that did not (controls), using RNA sequencing and regression analysis. Serum levels of 25 microRNAs were differentially expressed in cases versus controls within the first year after anthracycline treatment, as assessed by three different regression models (elastic net, Robinson and Smyth exact negative binomial test and random forest). MiR-4732-3p was the only microRNA identified in all regression models and was downregulated in patients that experienced cardiotoxicity. MiR-4732-3p was also present in neonatal rat cardiomyocytes and cardiac fibroblasts and was modulated by anthracycline treatment. A miR-4732-3p mimic was cardioprotective in cardiac and fibroblast cultures, following doxorubicin challenge, in terms of cell viability and ROS levels. Notably, administration of the miR-4732-3p mimic in doxorubicin-treated rats preserved cardiac function, normalized weight loss, induced angiogenesis, and decreased apoptosis, interstitial fibrosis and cardiac myofibroblasts. At the molecular level, miR-4732-3p regulated genes of TGFβ and Hippo signaling pathways. Overall, the results indicate that miR-4732-3p is a novel biomarker of cardiotoxicity that has therapeutic potential against anthracycline-induced heart damage.
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Mushagalusa, Ciza Arsène, Adandé Belarmain Fandohan, and Romain Glèlè Kakaï. "Random Forests in Count Data Modelling: An Analysis of the Influence of Data Features and Overdispersion on Regression Performance." Journal of Probability and Statistics 2022 (December 1, 2022): 1–21. http://dx.doi.org/10.1155/2022/2833537.
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Machine learning algorithms, especially random forests (RFs), have become an integrated part of the modern scientific methodology and represent an efficient alternative to conventional parametric algorithms. This study aimed to assess the influence of data features and overdispersion on RF regression performance. We assessed the effect of types of predictors (100, 75, 50, and 20% continuous, and 100% categorical), the number of predictors (p = 816 and 24), and the sample size (N = 50, 250, and 1250) on RF parameter settings. We also compared RF performance to that of classical generalized linear models (Poisson, negative binomial, and zero-inflated Poisson) and the linear model applied to log-transformed data. Two real datasets were analysed to demonstrate the usefulness of RF for overdispersed data modelling. Goodness-of-fit statistics such as root mean square error (RMSE) and biases were used to determine RF accuracy and validity. Results revealed that the number of variables to be randomly selected for each split, the proportion of samples to train the model, the minimal number of samples within each terminal node, and RF regression performance are not influenced by the sample size, number, and type of predictors. However, the ratio of observations to the number of predictors affects the stability of the best RF parameters. RF performs well for all types of covariates and different levels of dispersion. The magnitude of dispersion does not significantly influence RF predictive validity. In contrast, its predictive accuracy is significantly influenced by the magnitude of dispersion in the response variable, conditional on the explanatory variables. RF has performed almost as well as the models of the classical Poisson family in the presence of overdispersion. Given RF’s advantages, it is an appropriate statistical alternative for counting data.
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Bachmair, Sophie, Cecilia Svensson, Ilaria Prosdocimi, Jamie Hannaford, and Kerstin Stahl. "Developing drought impact functions for drought risk management." Natural Hazards and Earth System Sciences 17, no. 11 (November 16, 2017): 1947–60. http://dx.doi.org/10.5194/nhess-17-1947-2017.
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Abstract. Drought management frameworks are dependent on methods for monitoring and prediction, but quantifying the hazard alone is arguably not sufficient; the negative consequences that may arise from a lack of precipitation must also be predicted if droughts are to be better managed. However, the link between drought intensity, expressed by some hydrometeorological indicator, and the occurrence of drought impacts has only recently begun to be addressed. One challenge is the paucity of information on ecological and socioeconomic consequences of drought. This study tests the potential for developing empirical drought impact functions based on drought indicators (Standardized Precipitation and Standardized Precipitation Evaporation Index) as predictors and text-based reports on drought impacts as a surrogate variable for drought damage. While there have been studies exploiting textual evidence of drought impacts, a systematic assessment of the effect of impact quantification method and different functional relationships for modeling drought impacts is missing. Using Southeast England as a case study we tested the potential of three different data-driven models for predicting drought impacts quantified from text-based reports: logistic regression, zero-altered negative binomial regression (hurdle model), and an ensemble regression tree approach (random forest). The logistic regression model can only be applied to a binary impact/no impact time series, whereas the other two models can additionally predict the full counts of impact occurrence at each time point. While modeling binary data results in the lowest prediction uncertainty, modeling the full counts has the advantage of also providing a measure of impact severity, and the counts were found to be reasonably predictable. However, there were noticeable differences in skill between modeling methodologies. For binary data the logistic regression and the random forest model performed similarly well based on leave-one-out cross validation. For count data the random forest outperformed the hurdle model. The between-model differences occurred for total drought impacts and for two subsets of impact categories (water supply and freshwater ecosystem impacts). In addition, different ways of defining the impact counts were investigated and were found to have little influence on the prediction skill. For all models we found a positive effect of including impact information of the preceding month as a predictor in addition to the hydrometeorological indicators. We conclude that, although having some limitations, text-based reports on drought impacts can provide useful information for drought risk management, and our study showcases different methodological approaches to developing drought impact functions based on text-based data.
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Stapleton, Steven York, Anthony Ingle, and Timothy J. Gates. "Factors Contributing to Deer–Vehicle Crashes on Rural Two-Lane Roadways in Michigan." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 10 (May 15, 2019): 214–24. http://dx.doi.org/10.1177/0361198119848416.
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Deer–vehicle crashes (DVCs) continue to be a problem in the United States, with 1.2 million such crashes occurring annually. DVCs are a particular issue on two-lane rural highways in Michigan, accounting for more than 60% of crashes. Such a high proportion of DVCs limits the transferability of existing safety models, including those found in the Highway Safety Manual (HSM), that are often based on data from states with considerably lower proportions of deer crashes. To counter this, a cross-sectional analysis of deer crashes was performed using data from Michigan. The data were analyzed across four categories of rural two-lane roadways, including: state highways, federal aid county roadways, non-federal aid county roadways, and unpaved (gravel) county roadways. Mixed effects negative binomial regression models utilizing spatial and temporal random effects were generated separately for each of the rural two-lane roadway types. Results showed speed-related factors, including lane width, shoulder width, horizontal curvature, and peak level of service, had a significant effect on DVC occurrence for most types of rural two-lane roadways in Michigan. Wider lanes were associated with a greater occurrence of deer crashes, perhaps because of higher prevailing travel speeds. Conversely, horizontal curves with design speeds lower than the statutory speed limit were associated with fewer deer crashes, perhaps because of lower travel speeds through curves. Wider shoulders, which afford greater separation between the travel lanes and the roadside, were found to have significantly lower deer crash occurrence. The number of available hunting licenses did not have a consistent effect on DVCs.
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Stapleton, Steven Y., Anthony J. Ingle, Meghna Chakraborty, Timothy J. Gates, and Peter T. Savolainen. "Safety Performance Functions for Rural Two-Lane County Road Segments." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 52 (October 1, 2018): 226–37. http://dx.doi.org/10.1177/0361198118799035.
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Safety performance functions (SPFs) were developed for rural two-lane county roadway segments in Michigan. Five years of crash data (2011 to 2015) were analyzed for greater than 6,500 mi of rural county roadways, covering 29 of Michigan’s 83 counties and representing all regions of the state. Three separate models were developed to estimate annual deer-excluded total and injury crashes on rural county roadways: 1) paved federal-aid segments, 2) paved non-federal-aid segments, and 3) paved and gravel non-federal-aid segments with fewer than 400 vpd. To account for the unobserved heterogeneity associated with differing county design standards, mixed effects negative binomial models with a county-specific random effect were utilized. Not surprisingly, the county segment SPFs generally differed from traditional models generated using data from state-maintained roadways. County federal-aid roadways general showed greater crash occurrence than county non-federal-aid roadways, the Highway Safety Manual (HSM) two-lane rural roadways model, and rural state highways in Michigan. County non-federal-aid paved roadways showed crash occurrence rates that were remarkably similar to the HSM base rural two-lane roadway model, whereas gravel roadways showed greater crash occurrence rates. The presence of horizontal curves with design speeds below 55 mph had a strong association with the occurrence of total and injury crashes across all county road classes. Increasing driveway density was also found to be associated with increased crash occurrence. However, lane width, roadway surface width, and paved shoulder width had little to no impact on total or injury crashes.
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Kumfer, Wesley, David Harkey, Bo Lan, Raghavan Srinivasan, Daniel Carter, Anusha Patel Nujjetty, Ana Maria Eigen, and Carol Tan. "Identification of Critical Intersection Angle through Crash Modification Functions." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 2 (February 2019): 531–43. http://dx.doi.org/10.1177/0361198119828682.
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A significant portion of both fatal and total crashes occurs at intersections in the United States. Skew angle may be a significant contributor to these crashes. This paper examines the effects of intersection angle on intersection safety performance. With seven years of crash data from Minnesota and five years of crash data from Ohio, random forest regression data mining and negative binomial regression models were developed to estimate crash modification functions at three-leg and four-leg stop-controlled intersections with two-lane and multilane major legs. Where possible, the results were compared between the two states and used to develop average crash modification function curves. This study shows that over half of the intersection types experience the highest number of predicted crashes when the intersection angle between roadway legs is between 50 degrees and 65 degrees. These results have practical implications for engineers and safety professionals. First, the crash modification function curves supplement and revise the guidance for intersection angle in the Highway Safety Manual and Policy on Geometric Design of Highways and Streets. Second, the functions offer new guidance to agencies planning intersection improvements. Third, the crash modification functions can be used to determine the safety effect of changes in intersection angle.
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Robertson, Gregory J., Molly Tomlik, G. Randy Milton, Glen J. Parsons, and Mark L. Mallory. "Increases in the Number of American Black Ducks Wintering in Nova Scotia, 1970–2015." Journal of Fish and Wildlife Management 8, no. 2 (September 1, 2017): 669–75. http://dx.doi.org/10.3996/032017-jfwm-031.
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Abstract Despite extensive conservation and management efforts, American black duck (Anas rubripes) populations remain below desired population levels. Researchers have noted declines at a number of wintering areas, but indications are that wintering populations in the northern part of the range are increasing. Intermittently between 1970 and 1989, and annually since 1992, wildlife biologists have flown aerial surveys of the entire coast of Nova Scotia, Canada, to count wintering waterfowl. This survey counted the total number of ducks seen in predefined lengths of coastline. We analyzed those survey data using generalized linear mixed models, over the entire time period (1970–2015) and in the recent time period (1992–2015, when surveys were done every year), across five general regions of Nova Scotia. We fit models using Bayesian methods with uninformative priors; models with negative binomial response distributions performed well. Due to the large variation in mean numbers of black ducks across the predefined lengths of coastline, we treated these blocks of coastline as a fixed effect, while annual trend (slope) was modeled as a random effect to account for variation in annual trend across blocks of coastline. Results were similar between the entire time series (1970–2015) or the most recent and more complete time series (1992–2015). In general, numbers of wintering black ducks in Nova Scotia increased (1.0–16.0%/y) and increases were significant (Bayesian credible intervals did not bound 0) in four of five regions. Increasing numbers in Nova Scotia are consistent with other observations of increasing wintering numbers at the northern range of American black ducks and may indicate a shift in the wintering range that has been ongoing for decades. Future habitat management actions will benefit from consideration of regional trends and the distributional change of black duck.
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Vaisman, Alon, Grace Bannerman, John Matelski, Kathryn Tinckam, and Susy S. Hota. "Out of sight, out of mind: a prospective observational study to estimate the duration of the Hawthorne effect on hand hygiene events." BMJ Quality & Safety 29, no. 11 (March 9, 2020): 932–38. http://dx.doi.org/10.1136/bmjqs-2019-010310.
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BackgroundHuman auditing has been the gold standard for evaluating hand hygiene (HH) compliance but is subject to the Hawthorne effect (HE), the change in subjects’ behaviour due to their awareness of being observed. For the first time, we used electronic HH monitoring to characterise the duration of the HE on HH events after human auditors have left the ward.MethodsObservations were prospectively conducted on two transplant wards at a tertiary centre between May 2018 and January 2019. HH events were measured using the electronic GOJO Smartlink Activity Monitoring System located throughout the ward. Non-covert human auditing was conducted in 1-hour intervals at random locations on both wards on varying days of the week. Two adjusted negative binomial regression models were fit in order to estimate an overall auditor effect and a graded auditor effect.ResultsIn total, 365 674 HH dispensing events were observed out of a possible 911 791 opportunities. In the adjusted model, the presence of an auditor increased electronic HH events by approximately 2.5-fold in the room closest to where the auditor was standing (9.86 events per hour/3.98 events per hour; p<0.01), an effect sustained across only the partial hour before and after the auditor was present but not beyond the first hour after the auditor left. This effect persisted but was attenuated in areas distal from the auditor (total ward events of 6.91*6.32–7.55, p<0.01). Additionally, there was significant variability in the magnitude of the HE based on temporal and geographic distribution of audits.ConclusionThe HE on HH events appears to last for a limited time on inpatient wards and is highly dynamic across time and auditor location. These findings further challenge the validity and value of human auditing and support the need for alternative and complementary monitoring methods.
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Gavin-Plagne, L., L. Boyer, A. Baudot, M. Guedes Teixeira, G. Louis, L. Commin, S. Buff, and T. Joly. "159 Laparoscopic insemination method in sheep allows the use of an animal protein-free and inexpensive freezing medium." Reproduction, Fertility and Development 32, no. 2 (2020): 206. http://dx.doi.org/10.1071/rdv32n2ab159.
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Animal-derived products are widely used in sperm cryopreservation for their cryoprotective properties. These components, however, must be replaced because of sanitary risks. STEMALPHA.CRYO3 (Ref. 5617, Stem Alpha), called CRYO3, is a chemically defined preservation medium currently used for freezing human tissue and adult stem cells. The aim of this study was to evaluate the effects of a CRYO3-based medium and of two cooling rates on invitro parameters and invivo fertility of ram sperm. Six rams (Blanche du Massif Central) were subjected to sperm collection four times using an artificial vagina. Sperm were split and frozen in three media: an egg yolk and milk-based medium (positive control), a CRYO3-based medium (tested medium), and a medium without additives (negative control). The two cooling rates were related to the distance between the straws and the surface of liquid nitrogen during the freezing process (5 and 20cm). Sperm membrane integrity (propidium iodide/SYBR-14), acrosome integrity (fluorescein isothiocyanate-peanut agglutinin/propidium iodide; FITC-PNA/PI), and mitochondrial membrane potential (JC-1) were assessed using flow cytometry, whereas functional membrane integrity was assessed using a hypo-osmotic swelling test and motion characteristics were evaluated using computer-assisted sperm analysis. Pregnancy rate, parturition rate, and prolificacy were evaluated after performing laparoscopic inseminations (n=75 ewes). Moreover, we characterised the freezing media thermodynamically using a differential scanning calorimeter. Statistical analyses were performed using R software. Invitro parameters were assessed using a mixed model including the time and the medium as fixed effects and the ram as a random effect. Pregnancy and parturition rates, following a binomial distribution, and prolificacy, assumed to follow a Poisson distribution, were analysed using generalised linear models, including the medium as a fixed effect and the ram as a random effect. Differences with P<0.05 were considered statistically significant. The cooling rates had no significant effect except on the wobble motion parameter. The positive control medium showed significantly higher results than the CRYO3-based medium and the negative control medium for all invitro parameters except for straightness motion parameter. Conversely, field trials showed no significant difference between the media for pregnancy rate (71, 64, and 74%), parturition rate (68, 61, and 74%) and prolificacy (2.0, 2.1, and 1.7), for the positive control, CRYO3-based medium, and the negative control, respectively. This study showed that the product, CRYO3, cannot replace egg yolk and milk in freezing extenders. Moreover, we showed that laparoscopic inseminations allowed a 74% parturition rate due to an easy and inexpensive medium comprising only a Tris buffer and glycerol. Although it could not be used on a large scale, this medium remains an option for international transport or long-term storage of genetic diversity.
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Hamzeie, Raha, Megat-Usamah Megat-Johari, Iftin Thompson, Timothy P. Barrette, Trevor Kirsch, and Peter T. Savolainen. "Examining Safety on Two-Lane and Multilane Highways in Consideration of Access Spacing." Transportation Research Record: Journal of the Transportation Research Board 2673, no. 11 (June 14, 2019): 388–97. http://dx.doi.org/10.1177/0361198119851725.
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Access management strategies, such as the introduction of minimum access point spacing criteria and turning movement restrictions, have been shown to be important elements in optimizing the operational and safety performance of roadway segments. The relationship between safety and these types of access policies is a complex issue, and the impacts of such features on traffic crashes is critical to the development of appropriate access management strategies. The purpose of this study was to provide a quantitative evaluation of how crash risk on multilane and two-lane highways varies with respect to access spacing in support of the development of a revised access management policy. Data were obtained for approximately 1,247 and 5,795 mi of segments across multilane and two-lane highways, respectively. Crash data were obtained for a five-year period from 2012 to 2016 and a series of random effect negative binomial regression models were estimated for each facility to examine the association between crash frequency, access point spacing, and traffic volume. For both facility types, crashes were found to increase consistently as the average spacing of access points along road segments decreased. Crash rates were highest when consecutive accesses were within 150 ft of one another and the frequency of crashes decreased substantively as spacing was increased to 300 ft and, particularly, 600 ft. With spacing beyond 600 ft, crash rates continued to decrease, although these improvements were less pronounced than at the lower range of values. These findings were generally consistent on multilane and two-lane highways.
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Jatmiko, Irwan, Humber Andrade, and Budi Nugraha. "DELTA MODEL APPROACH FOR CPUE STANDARDIZATION OF SWORDFISH (Xiphias gladius Linnaeus, 1978) CAUGHT BY INDONESIAN LONGLINE FLEET IN THE EASTERN INDIAN OCEAN." Indonesian Fisheries Research Journal 23, no. 1 (October 17, 2017): 7. http://dx.doi.org/10.15578/ifrj.23.1.2017.7-15.
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Relative abundance indices as calculated based on commercial catches are the input data to run stock assessment models to gather useful information for decision making in fishery management. A Generalized Linear Model (GLM) was used to calculate relative abundance indices and effect of longline fishing gear configuration. Data were collected by a scientific observer program from August 2005 to November 2013. Most of the boats monitored were based in the Benoa Port, Bali. Catches are often equal to zero because swordfish is a bycatch for Indonesian longline fleets. Therefore, a hurdle model and a binomial distribution was used to model the proportion of positive catch rates, while a gamma distribution were used to model the positive longline sets. Correlations between the proportion of positive sets and year () and quarter () were weak. However, linear correlation between the proportion of positive sets and the length of branch lines () and number of hooks between floats () were negative and significant. The probability of success is higher for surface longline with small number of hooks and short branch lines. Models with year in interactions as random effects did not converge. Models with year in interactions as fixed effects did converge, but the estimation of standard errors of year coefficients were high. Meaningful estimations were obtained only when using the simplest model, in which year is not in interactions. The low proportional decrease of deviance indicates that most of the variability of catch rates of swordfish caught by Indonesian longline boats are not related to year, quarter, number of hooks between floats and the length of branch lines. Other variables and information, like the daytime while the longlines deployed in the water (day or night), type of bait, size and type of hooks, and if the fishermen use light-sticks to attract the fish, are necessary to better understand the catch rate, and improve the estimations of the relative abundance indices.
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Yang, Shaoyang, Zhaofei Fan, Xia Liu, Andrew Ezell, Martin Spetich, Scott Saucier, Sami Gray, and Scott Hereford. "Effects of Prescribed Fire, Site Factors, and Seed Sources on the Spread of Invasive Triadica sebifera in a Fire-Managed Coastal Landscape in Southeastern Mississippi, USA." Forests 10, no. 2 (February 19, 2019): 175. http://dx.doi.org/10.3390/f10020175.
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In the Gulf of Mexico coastal region, prescribed fire has been increasingly used as a management tool to restore declining native ecosystems, but it also increases the threat posed by biological invasion, since the treated sites are more susceptible to invasive species such as Chinese tallow (Triadica sebifera). We chose Mississippi Sandhill Crane National Wildlife Refuge (MSCNWR), a fire-managed landscape, to examine the potential effect of prescribed fire and landscape/community features on tallow invasion and spread. We took a complete survey of roadways and fire lines for tallow and measured a systematic sample of 144 10 × 3 m2 rectangular plots along two selected roadways and a simple random sample of 56 0.04-ha circular plots across burn units. We used pair correlation function for marked point pattern data, zero-inflated negative binomial models for count data, as well as multivariate Hotelling’s T2 test, to analyze the effect of prescribed fire and landscape/community characteristics on tallow invasion and spread along habitat edges and into interiors. Our results show that tallow spread along habitat edges and into interiors in a spatially clustered pattern. Tallow invasion risk decreases with the distance to seed trees and shrub coverage, and with the time since last fire if seed trees are outside the effective seed dispersal range (~300 m), but increases with the time since last fire if seed trees are within the effective seed dispersal range. Tallow seedling (≤2 years old) densities increase with the time since last fire and with increasing overstory tree basal area, but decrease with the distance to seed trees. Tallow-invaded interior plots have significantly shorter mean fire return intervals (2.7 years), lower shrub coverage (8.6%), and are closer to edges (20.3 m) than non-invaded plots (4.3 years, 18.4%, 167.6 m, respectively).
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Kolla, B., B. J. Coombes, T. I. Morgenthaler, and M. P. Mansukhani. "0173 Spring Forward, Fall Back: Increased Patient Safety-Related Adverse Events Following the Spring Time Change." Sleep 43, Supplement_1 (April 2020): A69. http://dx.doi.org/10.1093/sleep/zsaa056.171.
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Abstract Introduction “Spring forward,” the start of daylight savings time (DST) reduces sleep opportunity by an hour. The resulting sleep deprivation in healthcare workers can increase the potential for medical errors. We examined the change in patient safety-related adverse events (AEs) following the time change in both spring and fall. Methods Self-reported AEs that occurred 7 days prior to and following the spring and fall time changes for years 2010–2017 in a large healthcare organization were ascertained. AEs likely resulting from human errors were identified. The change in the number of AEs (all AEs or restricted to those resulting from human error) following the spring and fall time change were modeled using negative binomial mixed models using a random effect to correct for non-independent observations in consecutive. Results Over the 8 year period, there were more AEs (all and human) in the 7 days following the change in time both in spring (All: 2812 V. 2699; Human: 1902 V. 1625) and fall (All: 3207 V. 3007; Human: 2189 V. 2087). However, the only statistically significant increase was for the estimated 18% increase in human errors following time change in spring (95% CI: 6% to 34%; p = 0.004). The 18% AE increase in spring was also significantly greater than the 5% increase in AE in fall (p = 0.018). Conclusion There is a significant increase in human error related AEs following the “spring forward” clock change which can jeopardize patient safety. Based on safety considerations, DST might best be eliminated; alternatively, policy makers and healthcare organizations should evaluate measures to mitigate the increased risk during this period. Support NA
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Sousa Filho, J. Firmino de, Uriel M. Silva, Larissa L. Lima, Aureliano S. S. Paiva, Gervásio F. Santos, Roberto F. S. Andrade, Nelson Gouveia, et al. "Association of urban inequality and income segregation with COVID-19 mortality in Brazil." PLOS ONE 17, no. 11 (November 15, 2022): e0277441. http://dx.doi.org/10.1371/journal.pone.0277441.
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Socioeconomic factors have exacerbated the impact of COVID–19 worldwide. Brazil, already marked by significant economic inequalities, is one of the most affected countries, with one of the highest mortality rates. Understanding how inequality and income segregation contribute to excess mortality by COVID–19 in Brazilian cities is essential for designing public health policies to mitigate the impact of the disease. This paper aims to fill in this gap by analyzing the effect of income inequality and income segregation on COVID–19 mortality in large urban centers in Brazil. We compiled weekly COVID–19 mortality rates from March 2020 to February 2021 in a longitudinal ecological design, aggregating data at the city level for 152 Brazilian cities. Mortality rates from COVID-19 were compared across weeks, cities and states using mixed linear models. We estimated the associations between COVID-19 mortality rates with income inequality and income segregation using mixed negative binomial models including city and week-level random intercepts. We measured income inequality using the Gini index and income segregation using the dissimilarity index using data from the 2010 Brazilian demographic census. We found that 88.2% of COVID–19 mortality rates variability was between weeks, 8.5% between cities, and 3.3% between states. Higher-income inequality and higher-income segregation values were associated with higher COVID–19 mortality rates before and after accounting for all adjustment factors. In our main adjusted model, rate ratios (RR) per 1 SD increases in income inequality and income segregation were associated with 17% (95% CI 9% to 26%) and 11% (95% CI 4% to 19%) higher mortality. Income inequality and income segregation are long-standing hallmarks of large Brazilian cities. Risk factors related to the socioeconomic context affected the course of the pandemic in the country and contributed to high mortality rates. Pre-existing social vulnerabilities were critical factors in the aggravation of COVID–19, as supported by the observed associations in this study.
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Davelaar, Morgan Van, David R. Notter, D. Lee Wright, Anna M. Zajac, Scott P. Greiner, and Heather L. Bradford. "163 Annual differences in fecal egg counts in a forage-based ram test." Journal of Animal Science 97, Supplement_3 (December 2019): 172. http://dx.doi.org/10.1093/jas/skz258.354.
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Abstract The objective was to determine the magnitude of yearly differences in parasite load in growing ram lambs. Data were obtained from the Southwest Virginia Agriculture Research and Extension Center in Glade Spring, VA. The center conducts a forage-based ram growth test during the summer where rams also undergo a parasite challenge. Data consisted of 488 Katahdin rams tested from 2012 to 2018. Rams were dewormed at delivery, and at the start of the test, each ram received an oral dose of 5,000 H. contortus larvae adjusted for body weight. Fecal egg count was measured 70 d later when rams were on average (SD) 200 (18) d old. Fecal egg counts were not normally distributed. The Box-Cox procedure indicated that a log transformation was appropriate, but the residuals were not normally distributed for several linear models. A zero-inflated negative binomial generalized linear mixed model was used for data analysis with the glmmTMB package in R. The model included fixed effects of centered and scaled weight, centered and scaled age, year, birth type, and rearing type, and the random effect of consignor. Birth type, rear type, and age were not significant (P > 0.10). The least square mean (SE) fecal egg counts by year were 344 (118) for 2012, 623 (214) for 2013, 574 (195) for 2014, 1,125 (409) for 2015, 745 (253) for 2016, 408 (142) for 2017, and 239 (86) for 2018. Differences in summer precipitation could affect average parasite load. Despite similar total summer precipitation, 2012 had 1 extremely wet month whereas, 2015 had consistent precipitation throughout the summer. We conclude that producers should not compare fecal egg counts across years because the overall average may be multiple-fold different from year to year. Ranking rams within year will be more effective to select for improved parasite resistance.
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Sánchez Viafara, J. A., G. Lopez de Vasconcelos, R. Maculan, N. Gomes Alves, and J. Camisão de Souza. "70 Does the addition of docosahexaenoic acid to in vitro systems during culture improve the quality of bovine embryos?" Reproduction, Fertility and Development 31, no. 1 (2019): 160. http://dx.doi.org/10.1071/rdv31n1ab70.
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The aims of this study were to decrease the apoptotic index and increase cryotolerance of bovine embryos produced in vitro with the addition of 1 µM docosahexaenoic acid (DHA). On Day 1, presumed zygotes were cultivated with 1µM DHA (Sigma, St. Louis, MO, USA; n=437), and without the agonist (control group; n=450). The cleavage rate (%) was evaluated on Day 2 and the development of blastocysts on Day 7. Embryos before and after vitrification were fixed for the TUNEL trial. After vitrification, the embryos were heated and re-cultivated to evaluate the hatching rate at 12, 24, 36, 48, 60, and 72h. A sample of re-cultivated embryos at 12h of DHA (n=5), and without the agonist (control group; n=6), was frozen for mass spectrometry (MALDI-MS). Statistical analyses of deviance were carried out considering generalized mixed linear models, and the effect of the collection day (block) was considered as random. For the count variables, the Poisson distribution and the log link function were considered. In the cases of variables represented by rates, binomial distribution and the logit link function were used. In the study of cryotolerance, ANOVA of the hatching rate for each one of the times evaluated was carried out. In cases of significance of the effect of treatments, the Dunnett test was applied to compare treatments. Multivariate and univariate statistical models were used for analysis of MALDI-MS. All analyses were made using the GLIMMIX procedure of the SAS software (SAS Institute Inc., Cary, NC, USA). The cleavage rate was not different between the groups (P>0.05) and the production of blastocysts was lower in the DHA group (P<0.05). The number of cells per embryo was higher (P<0.05) by the addition of 1μM DHA in blastocysts pre- and post-vitrification. The rate of total and internal cell mass apoptosis in fresh embryos (11.73 and 15.98%) increased compared with the control group (9.62% and 11.03%, respectively). The proportion of internal cell mass in fresh embryos decreased in the DHA group (39.93%) compared with the control group (57.00%). Hatching rates at 48, 60, and 72h after devitrification in the group treated with 1μM DHA were not different (P>0.05) compared with the control group. Phosphatidylcholine [phosphatidylcholine (32: 0)+H] was more abundant (P<0.05) in embryos cultured with DHA, and thus was considered as a negative apoptosis biomarker. In conclusion, the use of 1μM DHA in vitrification of bovine embryos impairs embryonic quality and development under the conditions of the present study. Research was supported by CAPES, FAPEMIG, PPGCV/UFLA, EVUFMG, CENATTE EMBRIÕES.
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Hasler, Brant, Jessica Graves, Meredith Wallace, Stephanie Claudatos, Fiona Baker, and Duncan Clark. "610 Self-Reported Sleep and Circadian Characteristics Predict Future Substance Use: A Longitudinal Analysis from the NCANDA Study." Sleep 44, Supplement_2 (May 1, 2021): A240. http://dx.doi.org/10.1093/sleep/zsab072.608.
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Abstract Introduction Growing evidence indicates that sleep characteristics predict later substance use and related problems during adolescence and young adulthood. However, most prior studies have assessed a limited range of sleep characteristics, studied only a narrow age span, and included relatively few follow-up assessments. Here, we used multiple years of data from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study, which spans the adolescent period with an accelerated longitudinal design, to examine whether multiple sleep characteristics in any year predict substance use the following year. Methods The sample included 831 participants (423 females; age 12–21 years at baseline) from NCANDA. Sleep variables included the previous year’s circadian preference, sleep quality, daytime sleepiness, timing of midsleep (weekday and weekend), and sleep duration (weekday and weekend). Each sleep variable’s association with the subsequent year’s substance use (cannabis use or alcohol binge severity) across years 1–5 was tested separately using generalized linear mixed models (zero-inflated Negative Binomial for cannabis; ordinal for binge severity) with age, sex, race, visit, parental education, previous year’s substance use (yes/no) as covariates and subject as a random effect. Results With regard to cannabis use, greater eveningness and shorter weekday sleep duration predicted an increased risk for additional days of cannabis use the following year, while greater eveningness and later weekend midsleep predicted a greater likelihood of any cannabis use the following year. With regard to alcohol binge severity, greater eveningness, greater daytime sleepiness, and shorter sleep duration (weekday and weekend) all predicted an increased risk for more severe alcohol bingeing the following year. Post-hoc stratified analyses indicated that some of these associations may differ between high school-age and college-age participants. Conclusion Our findings extend prior work, indicating that eveningness and later sleep timing, as well as shorter sleep duration, especially on weekdays, are risk factors for future cannabis use and alcohol misuse. These results underscore a need for greater attention to sleep characteristics as potential risk factors for substance use in adolescents and young adults and may inform future areas of intervention. Support (if any) Grants from NIH: R01AA025626 (Hasler) and U01AA021690 (Clark) and UO1 AA021696 (Baker & Colrain)
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Cheng, Renee, Avani Singh, Xu Zhang, Priyanka Nasa, Jin Han, Doris Alfaro, Laura Kavoliunaite, et al. "Outcomes in Vaso-Occlusive Crisis Treatment in the Emergency Department Vs. Acute Care Observation Center." Blood 136, Supplement 1 (November 5, 2020): 22–23. http://dx.doi.org/10.1182/blood-2020-137297.
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I NTRODUCTION: Acute painful vaso-occlusive crises (VOC) are the leading cause of emergency department (ED) encounters and hospital admissions for those with sickle cell disease (SCD). For SCD patients, the goal of the sickle cell acute care observation unit (ACOU) at University of Illinois Health (UIH) is to improve patient outcomes by providing immediate care for an uncomplicated VOC. At our urban hospital which cares for more than 500 adult SCD patients, a considerable portion of SCD patients, despite having access to the ACOU, continue to present to the ED for treatment of an uncomplicated VOC. In order to help improve our current system, this study investigated outcomes in SCD patients who receive care for an uncomplicated VOC in the ACOU versus the ED at UIH. METHODS: By querying the electronic medical record, a retrospective study was conducted to analyze outcomes of encounters from the ACOU and ED at UIH between October 2019 and December 2019, specifically including SCD patients ≥18 years old who received morphine for treatment of an uncomplicated VOC. Encounters for complicated VOCs such as acute chest syndrome and stroke were excluded. Endpoints collected include time to first dose of morphine, total milligrams (mg) of IV morphine equivalents given, number of total morphine doses, admission rates, subsequent hospital length of stay, and 30-day inpatient admission rates. Time to the first dose (log transformed) and total dose in mg were analyzed by linear mixed effects models. The number of doses and hospitalization days were analyzed by negative binomial mixed effects model. Admissions and 30-day admissions were analyzed by logistic mixed effects models. These models adjusted for age, gender, and severe Hb genotype (HbSS or HbS beta0-thalassemia) and treated patient identity as random effect. P values were obtained from Wald- test. RESULTS: The ACOU data set contains 394 patient encounters for 79 patients with a median age of 33 years (interquartile range [IQR], 28-40), 71% female, and 73% with severe sickle genotypes. The ED data set contains 391 patient encounters for 128 patients with a median age of 30 years (IQR, 26-41), 53% female, and 74% with severe sickle genotypes. In the ACOU, the median time to first dose of morphine was 49 minutes (IQR, 39-60) compared to 107 minutes (IQR, 71-194) in the ED. The time to first dose was significantly longer in the ED compared to the ACOU (eβ=2.5, p <2×10-16). There was no significant difference in the total number of morphine doses received nor the total mg of morphine received between the two locations. Admission rate from ACOU was 6.6% compared to 53% from ED (OR=0.019, p=2x10-16). Of those admitted, the median number of hospitalization days from the ACOU was 4 days (IQR, 2.3-5.8) and 4 days (IQR, 2.0-6.5) from the ED. There was no significant difference in hospitalization days (p=0.6). The 30-day admission rate was 55% from the ACOU compared to 58% from the ED. 30-day admission rate however had strong intra-patient correlation (i.e., a patient was likely re-admitted multiple times): 44% of patients from the ACOU had admissions within 30 days of their ACOU visit compared to 32% from the ED. Controlling for the intra-patient correlation, ACOU visits had a higher 30-day admission rate than ED visit (OR=2.8, p=0.0015). DISCUSSION: SCD patients treated for an uncomplicated VOC at the sickle ACOU at UIH had a significantly shorter time to initial dose of IV pain medication. The wait time in the ED before first dose of IV pain medication received was more than double than those treated in the ACOU. Patients treated for an uncomplicated VOC in ACOU and ED had similar hospitalization days without a statistically significant difference. The 30-day admission rate to the inpatient setting was comparable for those treated in the ED versus the ACOU. However, given that only 6.6% of patients from the ACOU were admitted during the study period, this suggests that most patients who use both the ED and ACOU tend to be subsequently admitted from the ED. SCD patients may be presenting to the ED for treatment of VOC if capacity in the ACOU is exceeded or are presenting outside of hours of operation (currently 2 shifts Monday through Saturday). Therefore, improving access to our ACOU by increasing capacity and hours of operation may subsequently also lead to a decrease in time to first dose of medication and decrease in the overall 30-day admission rate. Disclosures Gordeuk: Imara: Research Funding; CSL Behring: Consultancy, Research Funding; Global Blood Therapeutics: Consultancy, Research Funding; Novartis: Consultancy; Ironwood: Research Funding.
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Diaz-Corro, Karla J., Leyla Coronel Moreno, Suman Mitra, and Sarah Hernandez. "Assessment of Crash Occurrence Using Historical Crash Data and a Random Effect Negative Binomial Model: A Case Study for a Rural State." Transportation Research Record: Journal of the Transportation Research Board, July 27, 2021, 036119812110275. http://dx.doi.org/10.1177/03611981211027569.
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This work identifies factors that influence crash occurrence within a traffic analysis zone (TAZ) by accounting for location-specific effects and serial correlation in longitudinal crash data. This is accomplished by applying a random effect negative binomial (RENB) model. Unlike commonly used count models such as Poisson and negative binomial (NB), RENB accounts for heterogeneity and serial correlation in crash occurrence. An RENB was applied to 15 years of crash data in Arkansas with 1,817 TAZs. Four models were developed for total crashes and by severity (property damage only (PDO), injury, and fatal). RENB-estimated impacts were measured using the incidence rate ratio (IRR). The significant causal factors found to increase in observed crashes include: (i) average precipitation (a one-unit increase in average precipitation results in a 134% increase in total monthly crashes for a TAZ); (ii) average wind speed (16%); (iii) urban designation (7%); (iv) traffic volume (2%); and (v) total roadway mileage (1% for each functional class). Snow depth and days of sunshine were found to decrease the number of accidents by 15% and 2%, respectively. Employment and total population had no impact on crash occurrence. Goodness-of-fit comparisons show that RENB provides the best fit among Poisson and NB formulations. All four model diagnostics confirm the presence of over-dispersion and serial correlation indicating the necessity of RENB model estimation. The main contribution of this work is the identification of crash causal factors at the TAZ level for longitudinal data, which supports data-driven performance measurement requirements of recent federal legislation.
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Youssef, Ahmed H., Mohamed R. Abonazel, and Elsayed G. Ahmed. "Estimating the Number of Patents in the World Using Count Panel Data Models." Asian Journal of Probability and Statistics, March 19, 2020, 24–33. http://dx.doi.org/10.9734/ajpas/2020/v6i430167.
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In this paper, we review some estimators of count regression (Poisson and negative binomial) models in panel data modeling. These estimators based on the type of the panel data model (the model with fixed or random effects). Moreover, we study and compare the performance of these estimators based on a real dataset application. In our application, we study the effect of some economic variables on the number of patents for seventeen high-income countries in the world over the period from 2005 to 2016. The results indicate that the negative binomial model with fixed effects is the better and suitable for data, and the important (statistically significant) variables that effect on the number of patents in high-income countries are research and development (R&D) expenditures and gross domestic product (GDP) per capita.
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Amunyela, J. "An ecological adjusted random effect model for property crime in Windhoek, Namibia (2011-2016)." Namibian Journal for Research, Science and Technology, May 1, 2022, 81–92. http://dx.doi.org/10.54421/njrst.v4i1.90.
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Count data that are zero inflated are often analysed using Zero-Inflated Negative Binomial Generalized Linear Mixed Model (ZINB-GLMM) when observations are correlated in ways that require random effects. This study investigated ecological factors influencing the number of property crimes in Windhoek by using data obtained from the Windhoek police over the period of six consecutive years (2011 to 2016). The ecological concepts were measured at different levels of aggregation. Limited studies in Windhoek have considered analysing crime data on Generalized Linear Mixed Model via Template Model Builder (TMB) R-package. Crimes were counted with respect to Month, Season, Year, Location and Density. Property crime data contained more zeros than expected. When comparing models fitted, it was found that the Relative Risks (RR) were highly significant for models fitted via Negative Binomial distribution. By adopting a ZINB-GLMM, the study attempted to address the potential covariates for Property crimes. The study showed that most of the variation property crimes was due to locations. Crime was high during spring and winter time during the study period. The study further discovered that areas with high population densities had high crime intensity. Security patrols and surveillance should be stepped up in Windhoek in high density suburbs especially during winter and spring seasons.
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Shaaban, Ahmed Nabil, Bárbara Peleteiro, and Maria Rosario O. Martins. "Statistical models for analyzing count data: predictors of length of stay among HIV patients in Portugal using a multilevel model." BMC Health Services Research 21, no. 1 (April 21, 2021). http://dx.doi.org/10.1186/s12913-021-06389-1.
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Abstract Background This study offers a comprehensive approach to precisely analyze the complexly distributed length of stay among HIV admissions in Portugal. Objective To provide an illustration of statistical techniques for analysing count data using longitudinal predictors of length of stay among HIV hospitalizations in Portugal. Method Registered discharges in the Portuguese National Health Service (NHS) facilities Between January 2009 and December 2017, a total of 26,505 classified under Major Diagnostic Category (MDC) created for patients with HIV infection, with HIV/AIDS as a main or secondary cause of admission, were used to predict length of stay among HIV hospitalizations in Portugal. Several strategies were applied to select the best count fit model that includes the Poisson regression model, zero-inflated Poisson, the negative binomial regression model, and zero-inflated negative binomial regression model. A random hospital effects term has been incorporated into the negative binomial model to examine the dependence between observations within the same hospital. A multivariable analysis has been performed to assess the effect of covariates on length of stay. Results The median length of stay in our study was 11 days (interquartile range: 6–22). Statistical comparisons among the count models revealed that the random-effects negative binomial models provided the best fit with observed data. Admissions among males or admissions associated with TB infection, pneumocystis, cytomegalovirus, candidiasis, toxoplasmosis, or mycobacterium disease exhibit a highly significant increase in length of stay. Perfect trends were observed in which a higher number of diagnoses or procedures lead to significantly higher length of stay. The random-effects term included in our model and refers to unexplained factors specific to each hospital revealed obvious differences in quality among the hospitals included in our study. Conclusions This study provides a comprehensive approach to address unique problems associated with the prediction of length of stay among HIV patients in Portugal.
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"Determinants of Under-Five Mortality in Tach- Armachiho District, North Gondar, Ethiopia." Journal of Chemistry: Education Research and Practice 6, no. 2 (July 5, 2022). http://dx.doi.org/10.33140/jcerp.06.02.10.
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Background: Under-five mortality rate, often known by its acronym U5MR, indicates the probability of dying between birth and five years of age, expressed per 1,000 live births. Globally, 16,000 children under-five still die every day. Especially in Sub-Saharan Africa every 1 child in 12, dying before his or her fifth birthday. This study aims to identify the determinants of under-five mortality among women in child bearing age group of Tach-Armachiho district using count regression models. Methods: For achieving the objective, a two-stage random sampling technique (simple random sampling and systematic random sampling techniques in the first and second stages respectively) was used to select women respondents. The sample survey conducted in Tach-Armachiho district considered a total of 3815 households of women aged 15 to 49 years out of which the information was collected from 446 selected women through interviewer administrated questionnaire. Results: The descriptive statistics result showed that in the district 16.6% of mothers have faced the problem of at least one under-five death. In this study, Poisson regression, negative binomial, zero-inflated Poisson and zero-inflated negative binomial regression models were applied for data analysis. Each of these count models were compared by different statistical tests. So that, zero-inflated poisson regression model was found to be the best fit for the collected data. Results of the zero-inflated Poisson regression model showed that education of husband, source of water, mother occupation, kebele of mother, prenatal care, place of delivery, place of residence, wealth of house hold, average birth interval and average breast feeding were found to be statistically significant determinants of under-five mortality. Conclusions: In this study, it was found that the factors like average birth interval and average breast feeding were found to be statistically significant factors in both groups (not always zero category and always zero category) with under-five child deathwhereas education of husband, source of water, place of delivery, mother occupation and wealth index of the household have significant effect on under-five mortality under not always zero group. Place of residence, kebele of mother and prenatal care have a significant effect on under-five mortality in TachArmachiho district on inflated group
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Sakai-Bizmark, Rie, Hiraku Kumamaru, Dennys Estevez, Emily H. Marr, Edith Haghnazarian, Lauren E. M. Bedel, Laurie A. Mena, and Mark S. Kaplan. "Health-Care Utilization Due to Suicide Attempts Among Homeless Youth in New York State." American Journal of Epidemiology, February 12, 2021. http://dx.doi.org/10.1093/aje/kwab037.
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Abstract Suicide remains the leading cause of death among homeless youth. We assessed differences in health-care utilization between homeless and nonhomeless youth presenting to the emergency department or hospital after a suicide attempt. New York Statewide Inpatient and Emergency Department Databases (2009–2014) were used to identify homeless and nonhomeless youth aged 10–17 who utilized health-care services following a suicide attempt. To evaluate associations with homelessness, we used logistic regression models for use of violent means, intensive care unit utilization, log-transformed linear regression models for hospitalization cost, and negative binomial regression models for length of stay. All models adjusted for individual characteristics with a hospital random effect and year fixed effect. We identified 18,026 suicide attempts with health-care utilization rates of 347.2 (95% confidence interval (CI): 317.5, 377.0) and 67.3 (95% CI: 66.3, 68.3) per 100,000 person-years for homeless and nonhomeless youth, respectively. Length of stay for homeless youth was statistically longer than that for nonhomeless youth (incidence rate ratio = 1.53, 95% CI: 1.32, 1.77). All homeless youth who visited the emergency department after a suicide attempt were subsequently hospitalized. This could suggest a higher acuity upon presentation among homeless youth compared with nonhomeless youth. Interventions tailored to homeless youth should be developed.
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Hussen, Nuru Mohammed. "Application of two level count regression modeling on the determinants of fertility among married women in Ethiopia." BMC Women's Health 22, no. 1 (December 9, 2022). http://dx.doi.org/10.1186/s12905-022-02060-x.
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Abstract Background Fertility is the element of population dynamics that has a vital contribution toward changing population size and structure over time. The global population showed a major increment from time to time due to fertility. This increment was higher in south Asia and sub-Saharan Africa including Ethiopia. So this study targeted the factors affecting fertility among married women in Ethiopia through the framework of multilevel count regression analysis using the 2016 Ethiopian Demographic and Health Survey data. Methods Secondary data set on the birth records were obtained from the 2016 Ethiopia Demographic and Health Survey. The survey was a population-based cross-sectional study with a two-stage stratified cluster sampling design, where stratification was achieved by separating every region into urban and rural areas except the Addis Ababa region because it is entirely urban. A two-level negative binomial regression model was fitted to spot out the determinants of fertility among married women in Ethiopia. Results Among the random sample of 6141 women in the country, 27,150 births were recorded based on the 2016 Ethiopian Demographic and Health Survey report. The histograms showed that the data has a positively skewed distribution not extremely picked at the beginning. Findings from the study revealed that the contraception method used, residence, educational level of women, women’s age at first birth, and proceeding birth interval were the major predictors of fertility among married women in Ethiopia. Moreover, the estimates from the random effect result revealed that there is more fertility variation between the enumeration areas than within the enumeration areas. Conclusion Unobserved enumeration area fertility differences that cannot be addressed by a single-level approach were determined using a two-level negative binomial regression modeling approach. So, the application of standard models by ignoring this variation ought to embrace spurious results, then for such hierarchical data, multilevel modeling is recommended.
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Bhasin, Niti, Amit Soni, and Rabi Narayan Kar. "Do Institutional and Macroeconomic Factors Matter in IT companies M&As? Evidence from India." Business Perspectives and Research, November 5, 2020, 227853372096492. http://dx.doi.org/10.1177/2278533720964927.
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The liberalisation of the Indian economy, along with targeted policies of the Indian government for the information technology (IT) sector, has led to tremendous growth in this sector. While there has been substantial foreign investment in India in the IT sector through setting up of subsidiaries, joint ventures and acquisitions, Indian firms have also aggressively invested within and outside India through multiple modes. Among different sectors, the IT sector has been the most dominant in terms of mergers and acquisitions (M&As). This article focuses on host country (macroeconomic and institutional) determinants of M&As undertaken by Indian IT firms. Random effect negative binomial model in panel set up was selected to estimate the models. Four models were estimated as per the availability of data for 35–42 countries and for the period 2000–2015. The results for most of the variables in four models were very similar, reflecting robustness of the methodology. Most of the macroeconomic and institutional factors were found to be important determinants of the M&As by Indian IT companies. However, the economic recession of 2008–2009 was found to significantly reduce the M&A activities by Indian IT companies.
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Mun, Eun-Young, Zhengyang Zhou, David Huh, Lin Tan, Dateng Li, Emily E. Tanner-Smith, Scott T. Walters, and Mary E. Larimer. "Brief Alcohol Interventions are Effective through 6 Months: Findings from Marginalized Zero-inflated Poisson and Negative Binomial Models in a Two-step IPD Meta-analysis." Prevention Science, August 17, 2022. http://dx.doi.org/10.1007/s11121-022-01420-1.
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AbstractTo evaluate and optimize brief alcohol interventions (BAIs), it is critical to have a credible overall effect size estimate as a benchmark. Estimating such an effect size has been challenging because alcohol outcomes often represent responses from a mixture of individuals: those at high risk for alcohol misuse, occasional nondrinkers, and abstainers. Moreover, some BAIs exclusively focus on heavy drinkers, whereas others take a universal prevention approach. Depending on sample characteristics, the outcome distribution might have many zeros or very few zeros and overdispersion; consequently, the most appropriate statistical model may differ across studies. We synthesized individual participant data (IPD) from 19 studies in Project INTEGRATE (Mun et al., 2015b) that randomly allocated participants to intervention and control groups (N = 7,704 participants, 38.4% men, 74.7% White, 58.5% first-year students). We sequentially estimated marginalized zero-inflated Poisson (Long et al., 2014) or negative binomial regression models to obtain covariate-adjusted, study-specific intervention effect estimates in the first step, which were subsequently combined in a random-effects meta-analysis model in the second step. BAIs produced a statistically significant 8% advantage in the mean number of drinks at both 1–3 months (RR = 0.92, 95% CI = [0.85, 0.98]) and 6 months (RR = 0.92, 95% CI = [0.85, 0.99]) compared to controls. At 9–12 months, there was no statistically significant difference in the mean number of drinks between BAIs and controls. In conclusion, BAIs are effective at reducing the mean number of drinks through at least 6 months post intervention. IPD can play a critical role in deriving findings that could not be obtained in original individual studies or standard aggregate data meta-analyses.
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Deng, Zhaoju, Kun Wang, Chuang Xu, Jie Cao, and Chong Ma. "Prevalence and risk factors associated with high somatic cell count in Chinese dairy herds." Frontiers in Veterinary Science 9 (November 2, 2022). http://dx.doi.org/10.3389/fvets.2022.967275.
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This study aimed to (1) estimate the prevalence of cow-level high somatic cell count (SCC) in Chinese dairy herds and (2) identify potential factors associated with cow- and herd-level SCC variables. The monthly data on dairy herd improvement were collected from a total of 131 dairy herds in 11 provinces in China in 2019. Mixed models were constructed using the cow composite milk SCC and the variance of cow SCC as dependent variables separately and parity, seasons, days in milk (DIM), herd size, and farm types (family-owned vs. company-owned) as fixed effects, accounting for the nested random herd and cow effect. We used negative binomial regression using herd-level SCC-related variables, namely, monthly proportion of high SCC, monthly proportion of new high SCC, monthly proportion of chronic high SCC, and monthly proportion of new chronic high SCC as dependent variables separately against seasons, herd size, and farm types with the random herd effect. The overall average prevalence of high SCCs for each month per farm was 0.26 (2.5–97.5% quantile: 0–0.56). Company-owned farms performed better in herd SCC management. Seasons were significantly associated with all the aforementioned variables, and summer and autumn were the seasons associated with worse outcomes in herd SCCs. This study is the first to assess high SCC in a large number of Chinese dairy herds, which is useful for farms to tailor the on-farm mastitis control programs in China.
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Chakraborty, Meghna, and Timothy J. Gates. "Assessing Safety Performance on Urban and Suburban Roadways of Lower Functional Classification: An Evaluation of Minor Arterial and Collector Roadway Segments." Transportation Research Record: Journal of the Transportation Research Board, July 17, 2022, 036119812211064. http://dx.doi.org/10.1177/03611981221106480.
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Previous research of urban roadway safety performance has generally focused on roadways of high functional classifications, such as principal arterials. However, roadways with lower functional classifications, including minor arterials and collectors, typically possess characteristics that differ from those of higher roadway classes. Therefore, assumptions made on the general effect of the predictor variables from typical safety performance functions may not apply to lower roadway classes. To address these knowledge gaps, a safety performance evaluation of urban/suburban minor arterial and collector roadway segments was performed using traffic and roadway data along with 8 years of crash data from 189 mi of two-lane urban and suburban roadways in Washtenaw County, MI. Mixed-effects negative binomial models with a segment-specific random intercept were developed for minor arterial and collector road segments, considering total-, fatal and injury-, and property damage only crashes. In general, minor arterial roadways showed greater crash occurrence compared with collector roads. Posted speed limit had a significant positive association with crash frequency, and this effect increased when the speed limit exceeded 40 mph. The effect of speed limit was stronger on minor arterial segments and for fatal and injury crashes. Additionally, driveway density was found to have a significant effect on safety performance, which was stronger for commercial/industrial driveways compared with residential driveways and for collector roads compared with minor arterials, particularly when considering residential driveways. On-street parking was associated with lower crash occurrence, with a stronger effect on collector roadways, most likely because of greater parking turnover when compared with minor arterials.
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Chakraborty, Meghna, and Timothy J. Gates. "Association between Driveway Land Use and Safety Performance on Rural Highways." Transportation Research Record: Journal of the Transportation Research Board, November 12, 2020, 036119812096523. http://dx.doi.org/10.1177/0361198120965232.
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Rural roads are a critical component of the transportation network in the U.S., including Michigan, where county roads comprise of a majority of the state’s roadway mileage. The rates of fatal crashes on rural highways are substantially higher than that on urban roads. Previous research has investigated the safety impacts of driveway density, but the effects of driveway land use on rural roadway safety performance, particularly for county roadways, remains under-researched. This study analyzed the safety impacts of various classifications of driveway land utilization on rural two-lane state and county roads. Non-animal segment crashes from 2011 to 2015 were analyzed along with roadway data for over 5,556 mi of state highways and 5,890 mi of paved county segments from across Michigan. To account for the unobserved heterogeneity associated with varied county design standards and site characteristics, mixed-effects negative binomial regression with county- and site-specific random effects was utilized. Separate models were developed for state highways and paved county roads. The results indicated that commercial driveways possess a stronger effect on crash occurrence than other driveway land use types, including residential and industrial driveways. The effect of driveway density on crash frequency was also found to be stronger on state highways compared with the county roads. This study contributes to the limited body of knowledge in relation to the relationship between traffic safety and driveway land use for rural roadway segments, particularly for county roads, which typically possess design and travel characteristics that are considerably different from those of state highways.
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Schlag, Fenja, Andrea G. Allegrini, Jan Buitelaar, Ellen Verhoef, Marjolein van Donkelaar, Robert Plomin, Kaili Rimfeld, Simon E. Fisher, and Beate St Pourcain. "Polygenic risk for mental disorder reveals distinct association profiles across social behaviour in the general population." Molecular Psychiatry, February 28, 2022. http://dx.doi.org/10.1038/s41380-021-01419-0.
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AbstractMany mental health conditions present a spectrum of social difficulties that overlaps with social behaviour in the general population including shared but little characterised genetic links. Here, we systematically investigate heterogeneity in shared genetic liabilities with attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorders (ASD), bipolar disorder (BP), major depression (MD) and schizophrenia across a spectrum of different social symptoms. Longitudinally assessed low-prosociality and peer-problem scores in two UK population-based cohorts (4–17 years; parent- and teacher-reports; Avon Longitudinal Study of Parents and Children(ALSPAC): N ≤ 6,174; Twins Early Development Study(TEDS): N ≤ 7,112) were regressed on polygenic risk scores for disorder, as informed by genome-wide summary statistics from large consortia, using negative binomial regression models. Across ALSPAC and TEDS, we replicated univariate polygenic associations between social behaviour and risk for ADHD, MD and schizophrenia. Modelling variation in univariate genetic effects jointly using random-effect meta-regression revealed evidence for polygenic links between social behaviour and ADHD, ASD, MD, and schizophrenia risk, but not BP. Differences in age, reporter and social trait captured 45–88% in univariate effect variation. Cross-disorder adjusted analyses demonstrated that age-related heterogeneity in univariate effects is shared across mental health conditions, while reporter- and social trait-specific heterogeneity captures disorder-specific profiles. In particular, ADHD, MD, and ASD polygenic risk were more strongly linked to peer problems than low prosociality, while schizophrenia was associated with low prosociality only. The identified association profiles suggest differences in the social genetic architecture across mental disorders when investigating polygenic overlap with population-based social symptoms spanning 13 years of child and adolescent development.
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Aslibekyan, Stella, Anh N. Do, Marguerite R. Irvin, Bertha A. Hidalgo, Degui Zhi, Hemant K. Tiwari, Devin M. Absher, Jose M. Ordovas, and Donna K. Arnett. "Abstract P099: A Methylome- and Transcriptome-Wide Study of Dietary Fructose Intake in Humans." Circulation 135, suppl_1 (March 7, 2017). http://dx.doi.org/10.1161/circ.135.suppl_1.p099.
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Background: Animal model studies reported robust associations between fructose intake, a known determinant of metabolic health across species, and DNA methylation/ gene expression patterns. To date, these associations have not been comprehensively investigated in humans. Methods: Using DNA methylation data on ~470,000 cytosine-phosphate-guanine (CpG) sites in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN, n=991) quantified in CD4+ T-cells, we have interrogated the cross-sectional relationships between fructose intake (ascertained using a validated food frequency questionnaire) and epigenome-wide methylation. We fit linear mixed models adjusted for age, sex, study site, technical covariates (fixed effects) and family relatedness (random effect). We have supplemented the methylation analyses with a transcriptome-wide scan on 98 unrelated GOLDN participants with available RNASeq data in whole blood. For the RNASeq data analysis, we used negative binomial models of read counts as a function of fructose intake, adjusted for age, sex, study site, technical covariates (including differential white blood cell counts). Results and Conclusions: The top loci differentially methylated with respect to fructose intake mapped to SNED1 (regression coefficient +/- SE= 0.002 +/- 0.0005, P=5x10-6) and FARSB (regression coefficient +/- SE= 0.002 +/- 0.0004, P=5x10-6) on chromosome 2. SNED1 is an insulin responsive transcription factor that has previously been shown to be downregulated in the setting of metabolic syndrome. FARSB encodes an aminoacyl-tRNA synethetase implicated in cell growth. Additionally, two genes reached transcriptome-wide significance in the RNASeq analysis: MTATP8P1 (P=1x10-7) and PDXDC1 (P=6x10-7). Sequence variation in PDXDC1 (pyridoxal-dependent decarboxylase isoform) has previously been linked to lipid metabolism, while MTATP8P1 is a pseudogene for a mitochondrially encoded ATP synthase. Upon future replication and functional validation, our preliminary findings offer promising insights into the link between fructose intake and metabolic health.