Journal articles: 'Generalised lineal mixed-effects models'

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Lai, T. L. "A hybrid estimator in nonlinear and generalised linear mixed effects models." Biometrika 90, no. 4 (December 1, 2003): 859–79. http://dx.doi.org/10.1093/biomet/90.4.859.

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Cadigan, N. G., M. J. Morgan, and J. Brattey. "Improved estimation and forecasts of stock maturities using generalised linear mixed models with auto-correlated random effects." Fisheries Management and Ecology 21, no. 5 (June 25, 2014): 343–56. http://dx.doi.org/10.1111/fme.12080.

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Willis, Brian H., Mohammed Baragilly, and Dyuti Coomar. "Maximum likelihood estimation based on Newton–Raphson iteration for the bivariate random effects model in test accuracy meta-analysis." Statistical Methods in Medical Research 29, no. 4 (June 11, 2019): 1197–211. http://dx.doi.org/10.1177/0962280219853602.

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A bivariate generalised linear mixed model is often used for meta-analysis of test accuracy studies. The model is complex and requires five parameters to be estimated. As there is no closed form for the likelihood function for the model, maximum likelihood estimates for the parameters have to be obtained numerically. Although generic functions have emerged which may estimate the parameters in these models, they remain opaque to many. From first principles we demonstrate how the maximum likelihood estimates for the parameters may be obtained using two methods based on Newton–Raphson iteration. The first uses the profile likelihood and the second uses the Observed Fisher Information. As convergence may depend on the proximity of the initial estimates to the global maximum, each algorithm includes a method for obtaining robust initial estimates. A simulation study was used to evaluate the algorithms and compare their performance with the generic generalised linear mixed model function glmer from the lme4 package in R before applying them to two meta-analyses from the literature. In general, the two algorithms had higher convergence rates and coverage probabilities than glmer. Based on its performance characteristics the method of profiling is recommended for fitting the bivariate generalised linear mixed model for meta-analysis.

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Hao, Chengcheng, Dietrich von Rosen, and Tatjana von Rosen. "Influence diagnostics for count data under AB–BA crossover trials." Statistical Methods in Medical Research 26, no. 6 (November 23, 2015): 2938–50. http://dx.doi.org/10.1177/0962280215615597.

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This paper aims to develop diagnostic measures to assess the influence of data perturbations on estimates in AB-BA crossover studies with a Poisson distributed response. Generalised mixed linear models with normally distributed random effects are utilised. We show that in this special case, the model can be decomposed into two independent sub-models which allow to derive closed-form expressions to evaluate the changes in the maximum likelihood estimates under several perturbation schemes. The performance of the new influence measures is illustrated by simulation studies and the analysis of a real dataset.

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Mielenz, Norbert, Joachim Spilke, and Eberhard von Borell. "Analysis of correlated count data using generalised linear mixed models exemplified by field data on aggressive behaviour of boars." Archives Animal Breeding 57, no. 1 (January 29, 2015): 1–19. http://dx.doi.org/10.5194/aab-57-26-2015.

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Population-averaged and subject-specific models are available to evaluate count data when repeated observations per subject are present. The latter are also known in the literature as generalised linear mixed models (GLMM). In GLMM repeated measures are taken into account explicitly through random animal effects in the linear predictor. In this paper the relevant GLMMs are presented based on conditional Poisson or negative binomial distribution of the response variable for given random animal effects. Equations for the repeatability of count data are derived assuming normal distribution and logarithmic gamma distribution for the random animal effects. Using count data on aggressive behaviour events of pigs (barrows, sows and boars) in mixed-sex housing, we demonstrate the use of the Poisson »log-gamma intercept«, the Poisson »normal intercept« and the »normal intercept« model with negative binomial distribution. Since not all count data can definitely be seen as Poisson or negative-binomially distributed, questions of model selection and model checking are examined. Emanating from the example, we also interpret the least squares means, estimated on the link as well as the response scale. Options provided by the SAS procedure NLMIXED for estimating model parameters and for estimating marginal expected values are presented.

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Mielenz, Norbert, Joachim Spilke, and Eberhard von Borell. "Analysis of correlated count data using generalised linear mixed models exemplified by field data on aggressive behaviour of boars." Archives Animal Breeding 57, no. 1 (January 29, 2015): 1–19. http://dx.doi.org/10.7482/0003-9438-57-026.

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Abstract. Population-averaged and subject-specific models are available to evaluate count data when repeated observations per subject are present. The latter are also known in the literature as generalised linear mixed models (GLMM). In GLMM repeated measures are taken into account explicitly through random animal effects in the linear predictor. In this paper the relevant GLMMs are presented based on conditional Poisson or negative binomial distribution of the response variable for given random animal effects. Equations for the repeatability of count data are derived assuming normal distribution and logarithmic gamma distribution for the random animal effects. Using count data on aggressive behaviour events of pigs (barrows, sows and boars) in mixed-sex housing, we demonstrate the use of the Poisson »log-gamma intercept«, the Poisson »normal intercept« and the »normal intercept« model with negative binomial distribution. Since not all count data can definitely be seen as Poisson or negative-binomially distributed, questions of model selection and model checking are examined. Emanating from the example, we also interpret the least squares means, estimated on the link as well as the response scale. Options provided by the SAS procedure NLMIXED for estimating model parameters and for estimating marginal expected values are presented.

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Evans, Fiona H., and Jianxiu Shen. "Long-Term Hindcasts of Wheat Yield in Fields Using Remotely Sensed Phenology, Climate Data and Machine Learning." Remote Sensing 13, no. 13 (June 22, 2021): 2435. http://dx.doi.org/10.3390/rs13132435.

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Satellite remote sensing offers a cost-effective means of generating long-term hindcasts of yield that can be used to understand how yield varies in time and space. This study investigated the use of remotely sensed phenology, climate data and machine learning for estimating yield at a resolution suitable for optimising crop management in fields. We used spatially weighted growth curve estimation to identify the timing of phenological events from sequences of Landsat NDVI and derive phenological and seasonal climate metrics. Using data from a 17,000 ha study area, we investigated the relationships between the metrics and yield over 17 years from 2003 to 2019. We compared six statistical and machine learning models for estimating yield: multiple linear regression, mixed effects models, generalised additive models, random forests, support vector regression using radial basis functions and deep learning neural networks. We used a 50-50 train-test split on paddock-years where 50% of paddock-year combinations were randomly selected and used to train each model and the remaining 50% of paddock-years were used to assess the model accuracy. Using only phenological metrics, accuracy was highest using a linear mixed model with a random effect that allowed the relationship between integrated NDVI and yield to vary by year (R2 = 0.67, MAE = 0.25 t ha−1, RMSE = 0.33 t ha−1, NRMSE = 0.25). We quantified the improvements in accuracy when seasonal climate metrics were also used as predictors. We identified two optimal models using the combined phenological and seasonal climate metrics: support vector regression and deep learning models (R2 = 0.68, MAE = 0.25 t ha−1, RMSE = 0.32 t ha−1, NRMSE = 0.25). While the linear mixed model using only phenological metrics performed similarly to the nonlinear models that are also seasonal climate metrics, the nonlinear models can be more easily generalised to estimate yield in years for which training data are unavailable. We conclude that long-term hindcasts of wheat yield in fields, at 30 m spatial resolution, can be produced using remotely sensed phenology from Landsat NDVI, climate data and machine learning.

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Wehnert, Alexandra, Sven Wagner, and Franka Huth. "Effects of Pure and Mixed Pine and Oak Forest Stands on Carabid Beetles." Diversity 13, no. 3 (March 17, 2021): 127. http://dx.doi.org/10.3390/d13030127.

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The multiple-use approach to forestry applied in Germany aims to combine timber production and habitat management by preserving specific stand structures. We selected four forest stand types comprising (i) pure oak, (ii) equal oak–pine mixtures, (iii) single tree admixtures of oak in pine forest and (iv) pure pine. We analysed the effects of stand composition parameters on species representative of the larger carabid beetles (Carabus arvensis, C. coriaceus, C. hortensis, C. violaceus, Calosoma inquisitor). The main statistical methods used were correlation analyses and generalised linear mixed models. Cal. inquisitor was observed in pure oak forests exclusively. C. coriaceus and C. hortensis were absent from pure pine stands. High activity densities of C. arvensis and C. violaceus were observed in all four forest types. When assessed at the smaller scales of species crown cover proportions and spatial tree species effect zones, C. hortensis was found to be positively related to oak trees with a regular spatial distribution, whereas C. coriaceus preferred lower and more aggregated oak tree proportions. C. violaceus showed strong sex-specific tree species affinities. Information about preferences of carabid beetles is necessary for management activities targeting the adaptation of forest structures to habitat requirements.

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Adamec, Z. "Comparison of linear mixed effects model and generalized model of the tree height-diameter relationship." Journal of Forest Science 61, No. 10 (June 3, 2016): 439–47. http://dx.doi.org/10.17221/68/2015-jfs.

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Tan, Z. D., L. R. Carrasco, and D. Taylor. "Corrigendum to: Spatial correlates of forest and land fires in Indonesia." International Journal of Wildland Fire 30, no. 9 (2021): 732. http://dx.doi.org/10.1071/wf20036_co.

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Biomass fires in Indonesia emit high levels of greenhouse gases and particulate matter, key contributors to global climate change and poor air quality in south-east Asia. In order to better understand the drivers of biomass fires across Indonesia over multiple years, we examined the distribution and probability of fires in Sumatra, Kalimantan (Indonesian Borneo) and Papua (western New Guinea) over four entire calendar years (2002, 2005, 2011 and 2015). The 4 years of data represent years with El Niño and La Niña conditions and high levels of data availability in the study region. Generalised linear mixed-effects models and zero-inflated negative binomial models were used to relate fire hotspots and a range of spatial predictor data. Geographic differences in occurrences of fire hotspots were evident. Fire probability was greatest in mixed-production agriculture lands and in deeper, degraded peatlands, suggesting anthropogenic activities were strong determinants of burning. Drought conditions in El Niño years were also significant. The results demonstrate the importance of prioritising areas of high fire probability, based on land use and other predisposing conditions, in effective fire management planning.

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Tan, Z. D., L. R. Carrasco, and D. Taylor. "Spatial correlates of forest and land fires in Indonesia." International Journal of Wildland Fire 29, no. 12 (2020): 1088. http://dx.doi.org/10.1071/wf20036.

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Biomass fires in Indonesia emit high levels of greenhouse gases and particulate matter, key contributors to global climate change and poor air quality in south-east Asia. In order to better understand the drivers of biomass fires across Indonesia over multiple years, we examined the distribution and probability of fires in Sumatra, Kalimantan (Indonesian Borneo) and Papua (western New Guinea) over four entire calendar years (2002, 2005, 2011 and 2015). The 4 years of data represent years with El Niño and La Niña conditions and high levels of data availability in the study region. Generalised linear mixed-effects models and zero-inflated negative binomial models were used to relate fire hotspots and a range of spatial predictor data. Geographic differences in occurrences of fire hotspots were evident. Fire probability was greatest in mixed-production agriculture lands and in deeper, degraded peatlands, suggesting anthropogenic activities were strong determinants of burning. Drought conditions in El Niño years were also significant. The results demonstrate the importance of prioritising areas of high fire probability, based on land use and other predisposing conditions, in effective fire management planning.

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Quaglio, G., F. Cavallin, J. B. Nsubuga, P. Lochoro, D. Maziku, A. Tsegaye, G. Azzimonti, A. M. Kamunga, F. Manenti, and G. Putoto. "The impact of the COVID-19 pandemic on health service use in sub-Saharan Africa." Public Health Action 12, no. 1 (March 21, 2022): 34–39. http://dx.doi.org/10.5588/pha.21.0073.

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SETTING: Six hospitals in four sub-Saharan African countries.OBJECTIVE: To examine the indirect effects of COVID-19 on health service utilisation and to explore the risk of bias in studies on prediction models.DESIGN: Monthly data were analysed using interrupted time-series modelling. We used linear mixed-effect models for the analysis of antenatal care visits, institutional deliveries, vaccinations, outpatient visits and hospital admissions, and generalised linear mixed-effect models for hospital mortality.RESULTS: During 2018–2020, the six hospitals recorded a total of 57,075 antenatal care visits, 38,706 institutional deliveries, 312,961 vaccinations, 605,925 out-patient visits and 143,915 hospital admissions. The COVID-19 period was associated with decreases in vacci-nations (− 575 vaccinations, P < 0.0001), outpatient visits (− 700 visits, P < 0.0001) and hospital admission (− 102 admission, P = 0.001); however, no statistically significant effects were found for antenatal care visits (P = 0.71) or institutional deliveries (P = 0.14). Mortality rate increased by 2% per month in the pre-COVID-19 period; however, a decreasing trend (by 2% per month) was observed during the COVID-19 period (P = 0.004). Subgroup and sensitivity analyses broadly confirmed the main findings with only minor inconsistencies. A reduction in outpatient visits was also observed in hospitals from countries with a higher Stringency Index and in urban hospitals.CONCLUSIONS: The pandemic resulted in a reduction in health service utilisation. The decreases were less than anticipated from modelling studies.

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Flatley, Christopher, Kristen Gibbons, Cameron Hurst, Vicki Flenady, and Sailesh Kumar. "Cross-validated prediction model for severe adverse neonatal outcomes in a term, non-anomalous, singleton cohort." BMJ Paediatrics Open 3, no. 1 (March 2019): e000424. http://dx.doi.org/10.1136/bmjpo-2018-000424.

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ObjectiveThe aim of this study was to develop a predictive model using maternal, intrapartum and ultrasound variables for a composite of severe adverse neonatal outcomes (SANO) in term infants.DesignProspectively collected observational study. Mixed effects generalised linear models were used for modelling. Internal validation was performed using the K-fold cross-validation technique.SettingThis was a study of women that birthed at the Mater Mother’s Hospital in Brisbane, Australia between January 2010 and April 2017.PatientsWe included all term, non-anomalous singleton pregnancies that had an ultrasound performed between 36 and 38 weeks gestation and had recordings for the umbilical artery pulsatility index, middle cerebral artery pulsatility index and the estimated fetal weight (EFW).Main outcome measuresThe components of the SANO were: severe acidosis arterial, admission to the neonatal intensive care unit, Apgar score of ≤3 at 5 min or perinatal death.ResultsThere were 5439 women identified during the study period that met the inclusion criteria, with 11.7% of this cohort having SANO. The final generalised linear mixed model consisted of the following variables: maternal ethnicity, socioeconomic score, nulliparity, induction of labour, method of birth and z-scores for EFW and cerebroplacental ratio. The final model had an area under the receiver operating characteristic curve of 0.71.ConclusionsThe results of this study demonstrate it is possible to predict infants that are at risk of SANO at term with moderate accuracy using a combination of maternal, intrapartum and ultrasound variables. Cross-validation analysis suggests a high calibration of the model.

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Mykletun, Arnstein, Tarjei Widding-Havneraas, Ashmita Chaulagain, Ingvild Lyhmann, Ingvar Bjelland, Anne Halmøy, Felix Elwert, et al. "Causal modelling of variation in clinical practice and long-term outcomes of ADHD using Norwegian registry data: the ADHD controversy project." BMJ Open 11, no. 1 (January 2021): e041698. http://dx.doi.org/10.1136/bmjopen-2020-041698.

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IntroductionAttention-deficit/hyperactivity disorder (ADHD) is among the most common mental disorders in children and adolescents, and it is a strong risk factor for several adverse psychosocial outcomes over the lifespan. There are large between-country and within-country variations in diagnosis and medication rates. Due to ethical and practical considerations, a few studies have examined the effects of receiving a diagnosis, and there is a lack of research on effects of medication on long-term outcomes.Our project has four aims organised in four work packages: (WP1) To examine the prognosis of ADHD (with and without medication) compared with patients with other psychiatric diagnoses, patients in contact with public sector child and adolescent psychiatric outpatient clinics (without diagnosis) and the general population; (WP2) Examine within-country variation in ADHD diagnoses and medication rates by clinics’ catchment area; and(WP3) Identify causal effects of being diagnosed with ADHD and (WP4) ADHD medication on long-term outcomes.Method and analysisOur project links several nationwide Norwegian registries. The patient sample is all persons aged 5–18 years that were in contact with public sector child and adolescent psychiatric outpatient clinics in 2009–2011. Our comparative analysis of prognosis will be based on survival analysis and mixed-effects models. Our analysis of variation will apply mixed-effects models and generalised linear models. We have two identification strategies for the effect of being diagnosed with ADHD and of receiving medication on long-term outcomes. Both strategies rely on using preference-based instrumental variables, which in our project are based on provider preferences for ADHD diagnosis and medication.Ethics and disseminationThe project is approved by the Regional Ethics Committee, Norway (REC number 2017/2150/REC south-east D). All papers will be published in open-access journals and results will be presented in national and international conferences.Trial registration numbersISRCTN11573246 and ISRCTN11891971.

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Julia, Chantal, Nathalie Arnault, Cédric Agaësse, Morgane Fialon, Mélanie Deschasaux-Tanguy, Valentina A. Andreeva, Léopold K. Fezeu, et al. "Impact of the Front-of-Pack Label Nutri-Score on the Nutritional Quality of Food Choices in a Quasi-Experimental Trial in Catering." Nutrients 13, no. 12 (December 17, 2021): 4530. http://dx.doi.org/10.3390/nu13124530.

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The front-of-pack labelling Nutri-Score has recently been implemented as a policy measure to improve the healthiness of food choices. The aim of this study was to investigate the impact of the Nutri-Score label in catering. A quasi-experimental trial was conducted in France between 16 December 2019 and 13 March 2020 in two staff restaurants (one intervention and one control site) from the same company. After a control period of seven weeks, the Nutri-Score label was affixed on all proposed products in the intervention site. Overall effects of the intervention were investigated using a difference in difference approach with generalised linear models. Over the 13 weeks of the study, 2063 participants who frequented the restaurant cafeteria at least once were included (1268 and 795 in the intervention and control site, respectively), representing 36,114 meals. Overall, the intervention led to a significant improvement in the nutritional quality of meals (p = 0.008) and a significant reduction in the intake of calories, sugars and saturated fat (p < 0.0001). Mixed effects models showed a qualitative improvement of food choices initially, and an adaptation of the quantities consumed over time, suggesting for the first time longer-term effects of the label on dietary behaviour.

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Kranepuhl, Michaela, Detlef May, Edna Hillmann, and Lorenz Gygax. "Association of body condition with lameness in dairy cattle: a single-farm longitudinal study." Journal of Dairy Research 88, no. 2 (May 2021): 162–65. http://dx.doi.org/10.1017/s0022029921000297.

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AbstractThis research communication describes the relationship between the occurrence of lameness and body condition score (BCS) in a sample of 288 cows from a single farm that were repeatedly scored in the course of 9 months while controlling for confounding variables. The relationship between BCS and lameness was evaluated using generalised linear mixed-effects models. It was found that the proportion of lame cows was higher with decreasing but also with increasing BCS, increased with lactation number and decreased with time since the last claw trimming. This is likely to reflect the importance of sufficient body condition in the prevention of lameness but also raises the question of the impact of overcondition on lameness and the influence of claw trimming events on the assessment of lameness. A stronger focus on BCS might allow improved management of lameness that is still one of the major problems in housed cows.

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Snepsts, Guntars, Mara Kitenberga, Didzis Elferts, Janis Donis, and Aris Jansons. "Stem Damage Modifies the Impact of Wind on Norway Spruces." Forests 11, no. 4 (April 19, 2020): 463. http://dx.doi.org/10.3390/f11040463.

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Bark stripping caused by cervids can have a long-lasting negative effect on tree vitality. Such trees of low vitality might be more susceptible to other disturbances. The amplifying effects of disturbance interactions can cause significantly more damage to forest ecosystems than the individual effects of each disturbance. Therefore, this study aimed to assess the impact of bark stripping (stem damage) on the probability of wind damage and snapping height for Norway spruces (Picea Abies (L.) H. Karst.). In this study, we used the Latvian National Forest Inventory data from the period 2004–2018. In the analysis, we used data based on 32,856 trees. To analyse the data, we implemented a Bayesian binary logistic generalised linear mixed-effects model and the linear mixed-effects model. Our results showed that stem damage significantly increased the probability of wind damage and affected the snapping height of Norway spruces. Similarly, root damage, the slenderness ratio, the stand age, the stand density, the soil type, and the dominant tree species had a significant influence on the probability of wind damage. In both periods, trees with stem damage had significantly (p < 0.05) higher probability (odd ratio 1.68) to be wind damaged than trees without stem damage. The stem damaged Norway spruce trees snapped in the first 25% of the tree height, while trees without stem damage snapped around half (50%) of the tree height. Our results show that stem damage significantly alters the effect of wind damage on Norway spruces, suggesting that such damage must be incorporated into wind-risk assessment models.

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Valenzuela, Trinidad, Jeff S. Coombes, Teresa Liu-Ambrose, Yorgi Mavros, Nicole Kochan, Perminder S. Sachdev, Jeffrey Hausdorff, et al. "Study protocol for the BRAIN Training Trial: a randomised controlled trial of Balance, Resistance, And INterval training on cognitive function in older adults with mild cognitive impairment." BMJ Open 12, no. 12 (December 2022): e062059. http://dx.doi.org/10.1136/bmjopen-2022-062059.

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IntroductionEpidemiological evidence suggests that both poor cardiovascular fitness and low muscle mass or strength markedly increase the rate of cognitive decline and incident dementia in older adults. Results from exercise trials for the improvement of cognition in older adults with mild cognitive impairment (MCI) have reported mixed results. This is possibly due to insufficient exercise intensities. The aim of the Balance, Resistance, And INterval (BRAIN) Training Trial is to determine the effects of two forms of exercise, high-intensity aerobic interval training (HIIT) and high-intensity power training (POWER) each compared with a sham exercise control group on cognition in older adults with MCI.Methods and analysisOne hundred and sixty community-dwelling older (≥ 60 years) people with MCI have been randomised into the trial. Interventions are delivered supervised 2–3 days per week for 12 months. The primary outcome measured at baseline, 6 and 12 months is performance on a cognitive composite score measuring the executive domain calculated from a combination of computerised (NeuroTrax) and paper-and-pencil tests. Analyses will be performed via repeated measures linear mixed models and generalised linear mixed models of baseline, 6-month and 12-month time points, adjusted for baseline values and covariates selected a priori. Mixed models will be constructed to determine the interaction of GROUP × TIME.Ethics and disseminationEthical approval was obtained from the University of Sydney (HREC Ref.2017/368), University of Queensland (HREC Ref. 2017/HE000853), University of British Columbia (H16-03309), and Vancouver Coastal Health Research Institute (V16-03309) Human Research Ethics. Dissemination will be via publications, conference presentations, newsletter articles, social media, talks to clinicians and consumers and meetings with health departments/managers.It is expected that communication of results will allow for the development of more effective evidence-based exercise prescription guidelines in this population while investigating the benefits of HIIT and POWER on subclinical markers of disease.Trial registration numberACTRN12617001440314 Australian New Zealand Clinical Trials Registry.

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Schwab, Simon, Giuachin Kreiliger, and Leonhard Held. "Assessing treatment effects and publication bias across different specialties in medicine: a meta-epidemiological study." BMJ Open 11, no. 9 (September 2021): e045942. http://dx.doi.org/10.1136/bmjopen-2020-045942.

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ObjectivesTo assess the prevalence of statistically significant treatment effects, adverse events and small-study effects (when small studies report more extreme results than large studies) and publication bias (over-reporting of statistically significant results) across medical specialties.DesignLarge meta-epidemiological study of treatment effects from the Cochrane Database of Systematic Reviews.MethodsWe investigated outcomes from 57 162 studies from 1922 to 2019, and overall 98 966 meta-analyses and 5534 large meta-analyses (≥10 studies). Egger’s and Harbord’s tests to detect small-study effects, limit meta-analysis and Copas selection models to bias-adjust effect estimates and generalised linear mixed models were used to analyse one of the largest collections of evidence in medicine.ResultsMedical specialties showed differences in the prevalence of statistically significant results of efficacy and safety outcomes. Treatment effects from primary studies published in high ranking journals were more likely to be statistically significant (OR=1.52; 95% CI 1.32 to 1.75) while randomised controlled trials were less likely to report a statistically significant effect (OR=0.90; 95% CI 0.86 to 0.94). Altogether 19% (95% CI 18% to 20%) of the large meta-analyses showed evidence for small-study effects, but only 3.9% (95% CI 3.4% to 4.4%) showed evidence for publication bias after further assessment of funnel plots. Adjusting treatment effects resulted in overall less evidence for efficacy.ConclusionsThese results suggest that reporting of large treatment effects from small studies may cause greater concern than publication bias. Incentives should be created so that studies of the highest quality become more visible than studies that report more extreme results.

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Gude, Patricia H., Kingsford Jones, Ray Rasker, and Mark C. Greenwood. "Evidence for the effect of homes on wildfire suppression costs." International Journal of Wildland Fire 22, no. 4 (2013): 537. http://dx.doi.org/10.1071/wf11095.

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This paper uses wildfires in the Sierra Nevada area of California to estimate the relationship between housing and fire suppression costs. We investigated whether the presence of homes was associated with increased costs of firefighting after controlling for the effects of potential confounding variables including fire size, weather, terrain and human factors such as road access. This paper investigates wildfires in a way that other published studies have not; we analysed costs at the daily level, retaining information that would have been lost had we aggregated the data. We used linear mixed models to estimate the effects of homes on daily costs while incorporating within-fire variation. We conclude that the expected increase in the log daily cost with each unit increase in the log count of homes within 6 miles (~9.7 km) of an active fire is 0.07 (P = 0.005). The findings of this study are in agreement with most other previous empirical studies that have investigated the relationship between fire suppression costs and housing using cumulative fire costs and more generalised data on home locations. The study adds to mounting evidence that increases in housing lead to increases in fire suppression costs.

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Georgeto, Sergio Murilo, Rodrigo Antônio Carvalho Andraus, Ovídia Ignês Pires, Eros de Oliveira Junior, and Karen Barros Parron Fernandes. "Preoperative use of gabapentin for pain reduction in open surgeries under local anesthesia for idiopathic bilateral carpal tunnel syndrome." Research, Society and Development 10, no. 4 (April 22, 2021): e54410414506. http://dx.doi.org/10.33448/rsd-v10i4.14506.

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This article aims to evaluate the preoperative use of gabapentin in the control of intra- and postoperative pain in patients with idiopathic bilateral carpal tunnel syndrome (CTS). A prospective, randomised, double-blind study involving 45 subjects with severe CTS, 23 receiving treatment (gabapentin 600 mg) and 22 receiving placebo (control), who underwent an open surgical approach in one hand under local anaesthesia. Information related to the patients’ profile, safety of the surgical procedure, history of pain, adverse effects, numbness, and medications used were collected during the 14 days of the procedure and evaluated by Generalised Estimated Equations and Generalised Linear Mixed Models. The treatment and control groups were homogeneous regarding the patients’ profile and surgical procedure data. The patients who used gabapentin 600 mg had a better evaluation during surgery (d = 0.655), anaesthesia (d = 0.854), and on the first night of sleep (d = 1.323), and they reported a higher degree of satisfaction with the surgery after 14 days (d = 1.091). The treatment group reported decreased pain in the operated hand in a 24-hour period (r = 0.34, 95% CI: 0.223–0.457) and in the 14-day follow-up period (r = 0.412, 95% CI: 0.217–0.608). These results were not impacted by the medications used and remained consistent over time. The use of a single dose of gabapentin 600 mg in the preoperative period proved to be safe and effective in reducing postoperative pain, and the improvement was noticed by the patient.

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Ward, Madeleine C., Karen Crinall, Rebecca McDonald, William Crinall, James Aridas, Cheryl Leung, Danielle Quittner, Ryan J. Hodges, and Daniel L. Rolnik. "The kindness COVID-19 toolkit: a mixed-methods evaluation of a programme designed by doctors in training for doctors in training." BMJ Open 12, no. 11 (November 2022): e060575. http://dx.doi.org/10.1136/bmjopen-2021-060575.

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ObjectivesThe impact of a coronavirus disease (COVID-19)-specific professional development programme on the well-being of obstetrics and gynaecology (O&G) doctors in training (DiT) working during the pandemic.DesignA mixed-method evaluation of a single group pre–post test design study.SettingMelbourne, Australia between September 2020 and April 2021.Participants55 O&G DiT working across four healthcare sites of a major tertiary hospital in Victoria, Australia, were included in the programme.InterventionsThe delivery of a codesigned peer-to-peer programme, which identified and addressed the well-being goals of O&G DiT. Seven interactive workshops were run alongside the implementation of a number of participant-led wellness initiatives.Main outcome measuresRepeated-measures analysis of WHO Well-being Index (WHO-5) and Copenhagen Burnout Innovatory (CBI) scores across three time points during the programme. Multilevel generalised linear mixed-effects models with random intercept were fit to the data, both in the entire population (intention-to-treat) and restricted to those who attended the workshop (‘per-protocol’ analysis). Participatory experiences and programme learning were captured using the Most Significant Change (MSC) technique, which included inductive thematic analysis.ResultsWe demonstrated an overall 31.9% improvement in well-being scores (p=0.006). The MSC evaluation captured a shift in workplace culture as a result of the programme, with improvement across the domains of connection, caring, communication, confidence and cooperation.ConclusionsWe have successfully used a mixed-method approach to contextualise a productive programme to improve the well-being of COVID-19 front-line healthcare workers.

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Daley, Ellen M., Stephanie L. Marhefka, Wei Wang, Charlotte A. Noble, Helen Mahony, Saba Arzola, Ashley Singleton, et al. "Longitudinal evaluation of the Teen Outreach Programme: Impacts of a health promotion programme on risky sexual behaviours." Health Education Journal 78, no. 8 (June 21, 2019): 916–30. http://dx.doi.org/10.1177/0017896919857777.

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Objective: This study evaluated the longitudinal impact of the Teen Outreach Programme (TOP) on adolescent pregnancy, sexual behaviour, risky sex and sexual intentions in non-metropolitan high schools. Design: Pair-matched, cluster randomised controlled trial. Setting: Non-metropolitan public high schools in Florida, USA. Methods: TOP was evaluated against the standard school health curriculum content. Young people ( N = 3,836) enrolled in 26 schools were surveyed at baseline (2012), immediate post-programme (2013) and at 1-year follow-up (2014). Most youth were 14 years old and in ninth grade at baseline. Missing data were imputed using a sequential imputation procedure and analysis took place using generalised linear mixed-effects models with logit link function. Results: Post-programme, young people in the treatment group were less likely to report ever having sex, recent sex, recent sex without a condom or intention to have sex in the next year. At 1-year follow-up, programme participants were less likely to report ever having been pregnant or having got someone pregnant. When examining treatment effects by gender, statistically significant differences were found only for female programme participants. Conclusion: Although many protective factors dissipated by second follow-up and were primarily found among female programme participants, TOP has the potential to decrease risky sexual behaviour.

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Heinz, Judith, Christian Röver, Ghefar Furaijat, Yvonne Kaußner, Eva Hummers, Thomas Debray, Alastair D. Hay, et al. "Strategies to reduce antibiotic use in women with uncomplicated urinary tract infection in primary care: protocol of a systematic review and meta-analysis including individual patient data." BMJ Open 10, no. 10 (October 2020): e035883. http://dx.doi.org/10.1136/bmjopen-2019-035883.

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IntroductionUncomplicated urinary tract infection (UTI) in women is a common reason to present in general practice and is usually treated with antibiotics to reduce symptom severity and duration. Results of recent clinical trials indicate that non-antibiotic treatment approaches can also be effective. However, it remains unclear which patients would benefit from antibiotic treatment and which can effectively and safely be treated without antibiotics. This systematic review and meta-analysis aims to estimate the effect of treatment strategies to reduce antibiotic use in comparison with immediate antibiotic treatment and to identify prognostic factors and moderators of treatment effects. A further aim is to identify subgroups of patients benefiting from a specific therapy.Methods and analysisA systematic literature search will be performed to identify randomised controlled trials which investigated the effect of treatment strategies to reduce antibiotic use in female adults with uncomplicated UTI compared with immediate antibiotic treatment. Therefore, the primary outcome of the meta-analysis is incomplete recovery. Anonymised individual patient data (IPD) will be collected. Aggregate data will be used for pairwise comparisons of treatment strategies using meta-analysis models with random effects accounting for potential between-study heterogeneity. Potential effect moderators will be explored in meta-regressions. For IPD, generalised linear mixed models will be used, which may be adjusted for baseline characteristics. Interactions of baseline variables with treatment effects will be explored. These models will be used to assess direct comparisons of treatment, but might be extended to networks.Ethics and disseminationThe local institutional review and ethics board judged the project a secondary analysis of existing anonymous data which meet the criteria for waiver of ethics review. Dissemination of the results will be via published scientific papers and presentations. Key messages will be promoted for example, via social media or press releases.PROSPERO registration numberCRD42019125804.

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Hoffmann, Luke, Will Edwards, Paul H. York, and Michael A. Rasheed. "Richness of Primary Producers and Consumer Abundance Mediate Epiphyte Loads in a Tropical Seagrass System." Diversity 12, no. 10 (October 7, 2020): 384. http://dx.doi.org/10.3390/d12100384.

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Consumer communities play an important role in maintaining ecosystem structure and function. In seagrass systems, algal regulation by mesograzers provides a critical maintenance function which promotes seagrass productivity. Consumer communities also represent a key link in trophic energy transfer and buffer negative effects to seagrasses associated with eutrophication. Such interactions are well documented in the literature regarding temperate systems, however, it is not clear if the same relationships exist in tropical systems. This study aimed to identify if the invertebrate communities within a tropical, multispecies seagrass meadow moderated epiphyte abundance under natural conditions by comparing algal abundance across two sites at Green Island, Australia. At each site, paired plots were established where invertebrate assemblages were perturbed via insecticide manipulation and compared to unmanipulated plots. An 89% increase in epiphyte abundance was seen after six weeks of experimental invertebrate reductions within the system. Using generalised linear mixed-effect models and path analysis, we found that the abundance of invertebrates was negatively correlated with epiphyte load on seagrass leaves. Habitat species richness was seen to be positively correlated with invertebrate abundance. These findings mirrored those of temperate systems, suggesting this mechanism operates similarly across latitudinal gradients.

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Zhang, Xinyu, Dalei Yu, Guohua Zou, and Hua Liang. "Optimal Model Averaging Estimation for Generalized Linear Models and Generalized Linear Mixed-Effects Models." Journal of the American Statistical Association 111, no. 516 (October 1, 2016): 1775–90. http://dx.doi.org/10.1080/01621459.2015.1115762.

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Xu, Liang, Sik-Yum Lee, and Wai-Yin Poon. "Deletion measures for generalized linear mixed effects models." Computational Statistics & Data Analysis 51, no. 2 (November 2006): 1131–46. http://dx.doi.org/10.1016/j.csda.2005.11.009.

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Gomperts, Edward D., John Schwarz, Sharyne M. Donfield, Alice E. Lail, Jan Astermark, W. Keith Hoots, Cheryl A. Winkler, and Erik Berntorp. "The importance of genetic factors for the development of arthropathy: a longitudinal study of children and adolescents with haemophilia A." Thrombosis and Haemostasis 117, no. 02 (2017): 277–85. http://dx.doi.org/10.1160/th16-06-0440.

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SummaryHaemophilia A is a congenital bleeding disorder characterised by recurrent haemorrhages into the major joints. Haemophilic arthropathy is a well-established outcome of recurrent joint bleeding; however, it is clear that multiple factors determine the extent and severity of its occurrence. We sought to identify genetic factors related to abnormalities in range of motion (ROM) in the knees, ankles and elbows in a cohort of children and adolescents with haemophilia A not treated primarily with regular prophylaxis. Using data from the Haemophilia Growth and Development Study, we examined associations between 13,342 genetic markers and ROM scores measured at six-month intervals for up to seven years. As a first step, ordered logistic regression models were fit for each joint separately. A subset of SNP markers showing significant effects (p<0.01) on the right and left sides for at least two joints were included in a full model fit using a multivariate generalised linear mixed model assuming an ordinal response. The models contained all ROM scores obtained at all visits. Twenty-five markers analysed in the full model showed either increased or decreased risk of ROM abnormalities at the p<0.001 level. Several genes identified at either the first or second stage of the analysis have been associated with arthritis in a variety of large studies. Our results support the likelihood that risk for haemophilic arthropathy is associated with genetic factors, the identification of which holds promise for further advancing the individualisation of treatment.

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Sousa, Braian Lucas Aguiar, Alexandra Brentani, Cecilia Claudia Costa Ribeiro, Marisa Dolhnikoff, Sandra Josefina Ferraz Ellero Grisi, Ana Paula Scoleze Ferrer, and Alexandre Archanjo Ferraro. "Non-communicable diseases, sociodemographic vulnerability and the risk of mortality in hospitalised children and adolescents with COVID-19 in Brazil: a cross-sectional observational study." BMJ Open 11, no. 9 (September 2021): e050724. http://dx.doi.org/10.1136/bmjopen-2021-050724.

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ObjectivesTo analyse how previous comorbidities, ethnicity, regionality and socioeconomic development are associated with COVID-19 mortality in hospitalised children and adolescents.DesignCross-sectional observational study using publicly available data from the Brazilian Ministry of Health.SettingNationwide.Participants5857 patients younger than 20 years old, all of them hospitalised with laboratory-confirmed COVID-19, from 1 January 2020 to 7 December 2020.Main outcome measureWe used multilevel mixed-effects generalised linear models to study in-hospital mortality, stratifying the analysis by age, region of the country, presence of non-communicable diseases, ethnicity and socioeconomic development.ResultsIndividually, most of the included comorbidities were risk factors for mortality. Notably, asthma was a protective factor (OR 0.4, 95% CI 0.24 to 0.67). Having more than one comorbidity increased almost tenfold the odds of death (OR 9.67, 95% CI 6.89 to 13.57). Compared with white children, Indigenous, Pardo (mixed) and East Asian had significantly higher odds of mortality (OR 5.83, 95% CI 2.43 to 14.02; OR 1.93, 95% CI 1.48 to 2.51; OR 2.98, 95% CI 1.02 to 8.71, respectively). We also found a regional influence (higher mortality in the North—OR 3.4, 95% CI 2.48 to 4.65) and a socioeconomic association (lower mortality among children from more socioeconomically developed municipalities—OR 0.26, 95% CI 0.17 to 0.38)ConclusionsBesides the association with comorbidities, we found ethnic, regional and socioeconomic factors shaping the mortality of children hospitalised with COVID-19 in Brazil. Our findings identify risk groups among children that should be prioritised for public health measures, such as vaccination.

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van der Veest Viðarsson, Heimir. "Málnotkun sem mælikvarði á áhrif málstöðlunar: Skólaritgerðir úr Lærða skólanum í Reykjavík (1846–1904)." Orð og tunga 19 (June 1, 2017): 129–53. http://dx.doi.org/10.33112/ordogtunga.19.5.

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The Reykjavík Grammar School (1846–1904) has been widely regarded as a primary force in the implementation of standard language norms in Iceland. The present article attempts to test this hypothesis in a selection of 189 student essays from the grammar school, including a survey of the teachers’ corrections. Three linguistic variables were selected, both known from the prescriptivist tradition and corrected in the es-says: 1) the generic pronoun maður, 2) the finite verb in third (V3) rather than second position (V2), 3) the definite article sá vs. hinn. Based on a series of statistical tools, a log-likelihood test for the generic pronoun, generalised linear mixed-effects models and conditional random forests for verb placement and the definite article, it is argued that the use of non-standard variants correlates significantly with progression of study (grades 1–3 vs. 4–6) and/or graduation score (low vs. high). The small corpus size prevented an analysis along the lines of Hinrichs et al. (2015), who recommend testing whether the (non-)use of one stigmatised ariant also correlates with the (non-)use of other stigmatised variants. Here, the educative variables arguably fulfil a similar function, independently from observing frequency decrease over time. The results thus suggest that prescriptive efforts were, indeed, quite successful.

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Cheliotis, Katerina S., Christopher P. Jewell, Carla Solórzano, Britta Urban, Andrea M. Collins, Elena Mitsi, Sherin Pojar, et al. "Influence of sex, season and environmental air quality on experimental human pneumococcal carriage acquisition: a retrospective cohort analysis." ERJ Open Research 8, no. 2 (March 31, 2022): 00586–2021. http://dx.doi.org/10.1183/23120541.00586-2021.

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Streptococcus pneumoniae (pneumococcus) is the most commonly identified bacterial cause of pneumonia and the leading infectious cause of death in children under 5 years of age worldwide. Pneumococcal disease follows a seasonal pattern with increased incidence during winter. Pneumonia burden is also associated with poor air quality. Nasopharyngeal carriage of the bacterium is a pre-requisite of invasive disease.We aimed to determine if susceptibility to nasopharyngeal pneumococcal carriage varied by season and which environmental factors might explain such variation. We also evaluated the influence of sex on susceptibility of carriage. We collated data from five studies in which human volunteers underwent intranasal pneumococcal challenge. Generalised linear mixed-effects models were used to identify factors associated with altered risk of carriage acquisition, specifically climate and air-quality data.During 2011–2017, 374 healthy adults were challenged with type 6B pneumococcus. Odds of carriage were significantly lower in males (OR, 0.61; 95% CI, 0.40–0.92; p=0.02), and higher with cooler temperatures (OR, 0.79; 95% CI, 0.63–0.99; p=0.04). Likelihood of carriage was also associated with lower concentrations of local fine particulate matter concentrations (PM2.5) and increased local rainfall.In contrast to epidemiological series, experimental challenge allowed us to test propensity to acquisition during controlled exposures; immunological explanations for sex and climatic differences should be sought.

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Santana, Danilo Dias, Gilberto Kac, Pedro Paulo Teixeira dos Santos, Thainá Castro da Silva, Camila Benaim, Paula Guedes Cocate, Maria Beatriz Trindade de Castro, Berit Lilienthal Heitmann, and Amanda Rodrigues Amorim Adegboye. "Association between Pre-Pregnancy BMI and Inflammatory Profile Trajectories during Pregnancy and Postpartum in Brazilian Women with Periodontitis: The IMPROVE Trial." International Journal of Environmental Research and Public Health 19, no. 5 (February 25, 2022): 2705. http://dx.doi.org/10.3390/ijerph19052705.

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This study aimed to explore the association between pre-pregnancy BMI and longitudinal changes in inflammatory markers from the second trimester of pregnancy to 6–8 weeks postpartum in women with periodontitis. This is a secondary exploratory analysis of 68 women who took part in a feasibility clinical trial in Rio de Janeiro, Brazil. Inflammatory markers included C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-10 (IL-10), and matrix metalloproteinase-9 (MMP-9) blood concentrations at 11–22 (T0) and 30–36 gestational weeks (T1), and 6–8 weeks postpartum (T3). Longitudinal generalised linear mixed-effects models were used to identify possible associations between pre-pregnancy BMI and changes in concentrations of inflammatory markers. Pre-pregnancy excess weight (β = 4.39; 95% CI, 2.12–6.65) was significantly associated with increased CRP levels from pregnancy to postpartum. There were no significant associations between pre-pregnancy BMI and longitudinal changes in IL-6, IL-10 and MMP-9. Our findings provide evidence that a higher pre-pregnancy BMI may lead to increases in CRP levels during pregnancy in women with periodontitis, irrespective of the severity of clinical periodontal parameters. Further studies need to investigate if predictors of changes in inflammatory markers can be used as prognostic factors for gestational outcomes.

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Passos, Luiza. "How does captivity affect skin colour reflectance of golden mantella frogs?" Herpetological Journal, Volume 30, Number 1 (January 1, 2020): 13–19. http://dx.doi.org/10.33256/hj30.1.1319.

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Coloration is an important trait for social communication in amphibians, being used in intra- and intersexual signalling to express information about individual body condition and health state, amongst other things. The striking colour pattern exhibited by some anuran species are also used in “aposematic” signals to advertise unpalatability to predators. The aim of this study was to investigate how the captive environment affects the colour of golden mantella frogs by comparing captive reared frogs with wild conspecifics. A USB-2000 portable diode-array spectrometer and a xenon strobe light source were used to perform spectrophotometric measurements on captive and wild populations. Hue, chroma and brightness of skin colour were analysed as well as body condition using the scaled mass index. Analyses showed variation among populations, but significant differences were only found between captive and wild populations. Generalised linear mixed models were used to evaluate the effects of body condition on colour variation and showed that animals with lower body condition from one captive population had significantly different coloration than their wild counterparts. Importantly, one captive population was not greatly different in coloration from their wild counterparts – demonstrating that this problem is not inevitable in captivity. These results can have important implications for reintroduction programmes.

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Manguro, Griffins O., Carol Gichuki, Frances H. Ampt, Paul A. Agius, Megan SC Lim, Walter G. Jaoko, Margaret Hellard, et al. "HIV infections among female sex workers in Mombasa, Kenya: current prevalence and trends over 25 years." International Journal of STD & AIDS 31, no. 14 (October 25, 2020): 1389–97. http://dx.doi.org/10.1177/0956462420950571.

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Over 20 years, interventions have targeted HIV among female sex workers (FSWs) in Kenya given their central role in new infections. To determine the effects of these interventions, we assessed the prevalence and correlates of HIV among a random sample of FSWs and modelled prevalence estimates from studies since 1993. FSWs aged 16–34 years were enrolled through multi-stage sampling. Regression models identified correlates of HIV infection. Generalised linear mixed modelling estimated temporal changes in prevalence between 1993 and 2016. 882 FSWs were enrolled. Prevalence rose from 3.6% among 16–20-year-olds to 31.6% among 31–34-year-old FSWs. Those aged 31 to 34 years had greater odds of HIV compared to those 16 to 20 years (AOR 14.2, 95% CI, 5.5–36.8). Infection was less prevalent among FSWs with tertiary education compared to those with primary or no education (AOR 0.23, 95% CI, 0.07–0.78). There was an overall 30% reduction in prevalence from 1993 to 2016 with an average annual decline of 3%. About one in ten FSWs in Mombasa are currently infected with HIV. Considering FSWs’ central role in sustaining population-level infections, these initiatives require continued support, focusing on reducing transmission from older FSWs and those with less education.

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Yeap, Bu Beng, Ross James Marriott, Robert J. Adams, Leen Antonio, Christie M. Ballantyne, Shalender Bhasin, Peggy M. Cawthon, et al. "Androgens In Men Study (AIMS): protocol for meta-analyses of individual participant data investigating associations of androgens with health outcomes in men." BMJ Open 10, no. 5 (May 2020): e034777. http://dx.doi.org/10.1136/bmjopen-2019-034777.

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IntroductionThis study aims to clarify the role(s) of endogenous sex hormones to influence health outcomes in men, specifically to define the associations of plasma testosterone with incidence of cardiovascular events, cancer, dementia and mortality risk, and to identify factors predicting testosterone concentrations. Data will be accrued from at least three Australian, two European and four North American population-based cohorts involving approximately 20 000 men.Methods and analysisEligible studies include prospective cohort studies with baseline testosterone concentrations measured using mass spectrometry and 5 years of follow-up data on incident cardiovascular events, mortality, cancer diagnoses or deaths, new-onset dementia or decline in cognitive function recorded. Data for men, who were not taking androgens or drugs suppressing testosterone production, metabolism or action; and had no prior orchidectomy, are eligible. Systematic literature searches were conducted from 14 June 2019 to 31 December 2019, with no date range set for searches. Aggregate level data will be sought where individual participant data (IPD) are not available. One-stage IPD random-effects meta-analyses will be performed, using linear mixed models, generalised linear mixed models and either stratified or frailty-augmented Cox regression models. Heterogeneity in estimates from different studies will be quantified and bias investigated using funnel plots. Effect size estimates will be presented in forest plots and non-negligible heterogeneity and bias investigated using subgroup or meta-regression analyses.Ethics and disseminationEthics approvals obtained for each of the participating cohorts state that participants have consented to have their data collected and used for research purposes. The Androgens In Men Study has been assessed as exempt from ethics review by the Human Ethics office at the University of Western Australia (file reference number RA/4/20/5014). Each of the component studies had obtained ethics approvals; please refer to respective component studies for details. Research findings will be disseminated to the scientific and broader community via the publication of four research articles, with each involving a separate set of IPD meta-analyses (articles will investigate different, distinct outcomes), at scientific conferences and meetings of relevant professional societies. Collaborating cohort studies will disseminate findings to study participants and local communities.PROSPERO registration numberCRD42019139668.

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Sunandi, Etis, Khairil Anwar Notodiputro, and Bagus Sartono. "A STUDY OF GENERALIZED LINEAR MIXED MODEL FOR COUNT DATA USING HIERARCHICAL BAYES METHOD." MEDIA STATISTIKA 14, no. 2 (December 12, 2021): 194–205. http://dx.doi.org/10.14710/medstat.14.2.194-205.

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Poisson Log-Normal Model is one of the hierarchical mixed models that can be used for count data. Several estimation methods can be used to estimate the model parameters. The first objective of this study was to examine the performance of the parameter estimator and model built using the Hierarchical Bayes method via Markov Chain Monte Carlo (MCMC) with simulation. The second objective was applied the Poisson Log-Normal model to the West Java illiteracy Cases data which is sourced from the Susenas data on March 2019. In 2019, the incidence of illiteracy is a very rare occurrence in West Java Province. So that, it is suitable as an application case in this study. The simulation results showed that the Hierarchical Bayes parameter estimator through MCMC has the smallest Root Mean Squared Error of Prediction (RMSEP) value and the absolute bias is relatively mostly similar when compared to the Maximum Likelihood (ML) and Penalized Quasi-Likelihood (PQL) methods. Meanwhile, the empirical results showed that the fixed variable is the number of respondents who have a maximum education of elementary school have the greatest risk of illiteracy. Also, the diversity of census blocks significantly affects illiteracy cases in West Java 2019.

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Gafta, Dan, Annik Schnitzler, Déborah Closset-Kopp, and Vasile Cristea. "Neighbourhood-based evidence of tree diversity promotion by beech in an old-growth deciduousconiferous mixed forest (Eastern Carpathians)." Annals of Forest Research 64, no. 1 (June 29, 2021): 13–30. http://dx.doi.org/10.15287/afr.2021.2143.

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Neighbourhood models are useful tools for understanding the role of positive and negative interactions in maintaining the tree species diversity in mixed forests. Under such a presumption, we aimed at testing several hypotheses concerning the mechanisms of autogenic species coexistence in an old-growth, beech-fir-spruce stand, which is part of the Slătioara forest reserve (Eastern Carpathians). Univariate/bivariate spatial point pattern analyses, the individual tree species-area relationship, the species mingling analysis and generalised linear mixed models of neighbour interference were applied on data concerning the position and allometry of all saplings and trees occurring within a 0.24 ha plot. The monospecific distribution of either beech or spruce saplings did not support the spatial segregation hypothesis. There was no evidence of conspecific negative distance dependence, as no spatial segregation was detected between the saplings and trees of any species. Within 4 m-neighbourhood, the beech saplings appeared as diversity accumulators, which might be indicative of indirect facilitation (e.g., herd protection hypothesis). At tree stage, none of the three species showed either accumulator or repeller patterns in their neighbourhood with respect to sapling species richness. Signals of positive and negative interspecific association were found in tree-sized beech (at scales of 10 to 20 m) and spruce (at scales of 4 to 17 m), respectively. The former, highly interspersed pattern is in accordance with the hypothesis of positive complementary effects, whereas the latter, poorly intermingled pattern is probably linked to the unexpected, positive neighbouring effect of spruce trees on the stem growth of their conspecific saplings. Such self-favouring process might be due to a facilitative below-ground mechanism. Conversely, the beech saplings were suppressed through interference from the neighbouring conspecific trees. The beech appears to be the key promoter of tree species coexistence in the study forest stand, in contrast to the low interspersion of spruce in the overstorey leading to lower local tree diversity.

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McDonall, Jo, Richard de Steiger, John Reynolds, Bernice Redley, Patricia M. Livingston, Anastasia F. Hutchinson, and Mari Botti. "Patient activation intervention to facilitate participation in recovery after total knee replacement (MIME): a cluster randomised cross-over trial." BMJ Quality & Safety 28, no. 10 (April 11, 2019): 782–92. http://dx.doi.org/10.1136/bmjqs-2018-008975.

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BackgroundPatient participation in care is a fundamental element of safe and high-quality healthcare with the potential to enhance health outcomes and improve patient satisfaction.ObjectivesTo test the efficacy of a clinician-facilitated, bedside multimedia (MyStay) intervention designed to support patient participation in their recovery after total knee replacement surgery. The primary outcome was patients’ reported worst pain intensity on postoperative day 3. Secondary outcomes were patient activation, length of hospital stay, knee function and satisfaction with care.MethodsUnmasked, cluster randomised, four-period cross-over trial with a simultaneous process evaluation within in a large private, not-for-profit, metropolitan teaching hospital. Statistical analyses used linear mixed models with random effects for wards, cohorts within wards and patients within cohorts and fixed effects for treatment and period.Results241 patients were recruited between March 2014 and June 2015. Patients were admitted to intervention (104) or control (137) clusters. Intervention group patients reported significantly lower mean pain intensity scores on postoperative day 3 (6.1 vs 7.1, 95% CI −1.94 to −0.08, p=0.04). The percentages of patients who reported severe pain (score ≥7) were 43.7% and 64.2% in the intervention and control groups, respectively (χ2 9.89, p=0.002; generalised linear mixed model Wald test, p=0.05). Intervention group patients on average stayed in hospital one less day (5.3 vs 6.3, 95% CI 0.05 to 1.94, p=0.04), reported higher activation (45.1% vs 27.1% at level 4 activation) (p=0.04) and higher overall satisfaction with care (9.3 vs 8.6, 95% CI 1.09 to 0.219, p=0.01), and were more likely to refer family or friends to the health service (9.3 vs 8.7, 95% CI 1.07 to 0.13, p=0.02).ConclusionThe clinician-facilitated, MyStay bedside multimedia intervention enhanced patients’ activation and participation in their care after surgery; pain intensity and length of stay in hospital were reduced and patients were more satisfied with their care.Trial registrationACTRN12614000340639 (http://www.anzctr.org.au/default.aspx).

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El-Saeiti, Intesar N., and Khalil Mostafa ALsawi. "PERFORMANCE OF MIXED EFFECTS FOR CLUSTERED COUNTING DATA MODELS." Scientific Journal of Applied Sciences of Sabratha University 3, no. 2 (September 27, 2020): 34–41. http://dx.doi.org/10.47891/sabujas.v3i2.34-41.

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This article is concerned with hierarchical generalized linear models. It includes generalized linear models and generalized linear mixed models, which are related to linear models. In generalized linear mixed models, the dependent variable and the standard error follow any distribution from the exponential family, e.g. normal, Poisson, binomial, gamma, etc. We studied counting data, and then use the Poisson-gamma model,where the dependentvariable follows the Poisson distribution and the standard error follow the gamma distribution. Several estimation techniques can be used for generalized linear mixed model. In this paperthe hierarchical likelihood estimation technique was used to prove the performance of H-likelihood methodwhen thecounting data were balanced or unbalanced. Real data were used to test the performance of Poisson-gamma H-likelihood estimation method in case of balanced and unbalanced counting data.When real data used in the past research for another problem, it was noticed that the performance of the hierarchical likelihood estimation technique gave a close approximations in the event of balanced and unbalanced counting data, and the output of the technique was approximately equivalent in both instances.

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Jeemon, Panniyammakal, Salim Reethu, Sanjay Ganapathi, Lakshmipuram Rajappan Lakshmi Kanth, Eapen Punnoose, Jabir Abdullakutty, Shafeeq Mattumal, et al. "A multicentric, 2 × 2 factorial, randomised, open-label trial to evaluate the clinical effectiveness of structured physical activity training and cognitive behavioural therapy versus usual care in heart failure patients: a protocol for the PACT-HF trial." Wellcome Open Research 7 (August 12, 2022): 210. http://dx.doi.org/10.12688/wellcomeopenres.18047.1.

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Background: Heart failure (HF) is a multi-morbid chronic condition, which adversely affects the quality of life of the affected individual. Engaging the patient and their caregivers in self-care is known to reduce mortality, rehospitalisation and improve quality of life among HF patients. The PACT-HF trial will answer whether clinical benefits in terms of mortality and hospitalisation outcomes can be demonstrated by using a pragmatic design to explore the specific effects of physical activity, and cognitive behavioural therapy in HF patients in India. Methods: We will conduct a 2 × 2 factorial, randomized, open-label trial, which aims to see if rehabilitation strategies of structured physical activity training and cognitive behavioural therapy for depression and self-management reduce the risk of repeat hospitalisation and deaths in HF patients in India. Patients will be randomised to (1) physical activity + usual care (2) cognitive behaviour therapy + usual care, (3) physical activity + cognitive behaviour therapy + usual care, and (4) usual care at 1:1:1:1 ratio. Time to mortality will be the primary outcome. A composite of mortality and hospitalisation for HF will be the main secondary outcome. Additional secondary outcomes will include ‘days alive and out of hospital’, cumulative hospitalisation, quality of life, Minnesota Living with Heart Failure questionnaire score, depression score, six minutes walking distance, handgrip strength, and adherence to medicines and lifestyle. The effects of intervention on the primary outcome will be estimated from Cox proportional hazard models. For the continuous secondary outcome variables, differences between randomised groups will be estimated from linear mixed models or generalised estimating equations (GEE) as appropriate. Discussion: PACT-HF is designed to provide reliable evidence about the balance of benefits and risks conferred by physical activity and cognitive behavioural therapy-based cardiac rehabilitation for those with HF, irrespective of their initial disease severity.

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Von Tress, Mark. "Generalized, Linear, and Mixed Models." Technometrics 45, no. 1 (February 2003): 99. http://dx.doi.org/10.1198/tech.2003.s13.

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Cowles, Mary Kathryn. "Generalized, Linear, and Mixed Models." Journal of the American Statistical Association 101, no. 476 (December 1, 2006): 1724. http://dx.doi.org/10.1198/jasa.2006.s145.

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Mitchell, Lada. "Generalized, Linear, and Mixed Models." Journal of the Royal Statistical Society: Series D (The Statistician) 52, no. 2 (July 2003): 242–43. http://dx.doi.org/10.1111/1467-9884.00356.

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Weirich, Sebastian, Martin Hecht, and Katrin Böhme. "Modeling Item Position Effects Using Generalized Linear Mixed Models." Applied Psychological Measurement 38, no. 7 (May 30, 2014): 535–48. http://dx.doi.org/10.1177/0146621614534955.

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Liang, Hua. "Generalized partially linear mixed-effects models incorporating mismeasured covariates." Annals of the Institute of Statistical Mathematics 61, no. 1 (August 10, 2007): 27–46. http://dx.doi.org/10.1007/s10463-007-0146-0.

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Lavergne, Christian, Marie-José Martinez, and Catherine Trottier. "Empirical model selection in generalized linear mixed effects models." Computational Statistics 23, no. 1 (July 14, 2007): 99–109. http://dx.doi.org/10.1007/s00180-007-0071-y.

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Forster, Jonathan J., Roger C. Gill, and Antony M. Overstall. "Reversible jump methods for generalised linear models and generalised linear mixed models." Statistics and Computing 22, no. 1 (October 28, 2010): 107–20. http://dx.doi.org/10.1007/s11222-010-9210-3.

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Dai, Wei, Shaohua Xie, Rui Zhang, Xing Wei, Chuanmei Wu, Yuanqiang Zhang, Wenhong Feng, et al. "Developing and validating utility parameters to establish patient-reported outcome-based perioperative symptom management in patients with lung cancer: a multicentre, prospective, observational cohort study protocol." BMJ Open 9, no. 10 (October 2019): e030726. http://dx.doi.org/10.1136/bmjopen-2019-030726.

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Abstract:

IntroductionPatient-reported outcome-based symptom monitoring and alerting have been attractive for patient care after a tumour-removal surgery. However, the implementation parameters of this patient-centred symptom management system in perioperative patients with lung cancer are still lacking. We aim to develop a perioperative symptom scale (PSS) for monitoring, to determine the optimal time points for symptom assessment and to define the alert thresholds for medical intervention.Methods and analysisThis study will prospectively recruit 300 patients undergoing lung cancer surgery in six hospitals. The MD Anderson Symptom Inventory–Lung Cancer Module (MDASI-LC) is used to collect longitudinal symptom data preoperatively, daily postoperatively during in-hospital stay and weekly after discharge until 4 weeks or the start of postoperative oncological therapy. Symptoms that change significantly over time will be generated as the PSS. We will determine the optimal time points for follow-up using the generalised linear mixed-effects models. The MDASI-LC interference-measured functional status will be used as the anchor for the alert thresholds.Ethics and disseminationEthics Committee of Sichuan Cancer Hospital approved this study on 16 October 2017 (No. SCCHEC-02-2017-042). The manuscript is based on the latest protocol of Version 3.0, 15 September 2019. The results of this study will be presented at medical conferences and published in peer-reviewed journals.Trials registration numberNCT03341377.

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Searle, K. R., A. Blackwell, D. Falconer, M. Sullivan, A. Butler, and B. V. Purse. "Identifying environmental drivers of insect phenology across space and time: Culicoides in Scotland as a case study." Bulletin of Entomological Research 103, no. 2 (July 30, 2012): 155–70. http://dx.doi.org/10.1017/s0007485312000466.

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AbstractInterpreting spatial patterns in the abundance of species over time is a fundamental cornerstone of ecological research. For many species, this type of analysis is hampered by datasets that contain a large proportion of zeros, and data that are overdispersed and spatially autocorrelated. This is particularly true for insects, for which abundance data can fluctuate from zero to many thousands in the space of weeks. Increasingly, an understanding of the ways in which environmental variation drives spatial and temporal patterns in the distribution, abundance and phenology of insects is required for management of pests and vector-borne diseases. In this study, we combine the use of smoothing techniques and generalised linear mixed models to relate environmental drivers to key phenological patterns of two species of biting midges, Culicoides pulicaris and C. impunctatus, of which C. pulicaris has been implicated in transmission of bluetongue in Europe. In so doing, we demonstrate analytical tools for linking the phenology of species with key environmental drivers, despite using a relatively small dataset containing overdispersed and zero-inflated data. We demonstrate the importance of landcover and climatic variables in determining the seasonal abundance of these two vector species, and highlight the need for more empirical data on the effects of temperature and precipitation on the life history traits of palearctic Culicoides spp. in Europe.

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Marchewka, Joanna, Ina Beltrán de Heredia, Xavier Averós, Roberto Ruiz, Adroaldo J. Zanella, Julia Adriana Calderón Díaz, and Inma Estevez. "Behaviour of tail-docked lambs tested in isolation." Irish Journal of Agricultural and Food Research 55, no. 2 (December 1, 2016): 192–99. http://dx.doi.org/10.1515/ijafr-2016-0019.

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AbstractThe aims of the current study were to detect behavioural indicators of pain of tail-docked sheep tested in isolation and to determine the relationship between behaviour and the pain levels to which they were exposed. Twenty-four female lambs, randomly assigned to four pens, had their tail docked with a rubber ring (TD; n = 6) without pain control procedures, TD with anaesthesia (TDA; n = 6) or TD with anaesthesia and analgesia (TDAA; n = 6). Additionally, six lambs handled but without tail docking or application of pain relief measures were used as the control (C). On the day prior (Day –1) to the TD and on days 1, 3 and 5 post-procedure, each lamb was individually removed from its group and underwent a 2.5 min open field test in a separate pen. Frequencies of behaviours such as rest, running, standing, walking and exploring were directly observed. Frequencies of exploratory climbs (ECs) and abrupt climbs (ACs) over the testing pen’s walls were video-recorded. Data were analysed using generalised linear mixed models with repeated measurements, including treatment and day as fixed effects and behaviour on Day –1 as a linear covariate. Control and TDAA lambs stood more frequently than TD lambs. TD lambs performed significantly more ACs compared to all other treatment groups. No other treatment effects were detected. A day effect was detected for all behaviours, while the EC frequency was highest for all tail-docked lambs on Day 5. Findings suggest that standing, ACs and ECs could be used as potential indicators of pain in isolated tail-docked lambs. However, differences in ECs between treatments only appeared 3 d after tail docking.

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Journal articles on the topic 'Generalised lineal mixed-effects models'

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