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1

Ali, Mohamed Kaltum. "Perceived risk of cannabis use and cannabis use among Swedish youth : A quantitative study from a public health perspective." Thesis, Mälardalens högskola, Hälsa och välfärd, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55093.

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Background: Risk perception has been studied concerning the use of marijuana and it impacts the intention to use that specific substance. Aim: The aim was to study the association between the perceived risk of cannabis use and cannabis use among Swedish youth after controlling for gender, age, and education. The aim was also to study whether the association between the perceived risk of cannabis use and cannabis use was different according to gender. Method: The thesis project was based on data from the Flash Eurobarometer 330 - Youth Attitudes on Drugs. Results: When age and education were controlled for, both among Swedish youth and among male participants, the perceived risk had an association with cannabis use - higher risk perception entailed a lower use. Discussion: The association between the perceived risk of cannabis use and cannabis use appears to be due to the impact of risk perception on behaviour. Conclusion: By preserving the risk perception that Swedish youth have of cannabis, it may be possible to protect them from the potential harm that cannabis use cause.
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Masse, Marjolaine. "Risk factors for premorbid cannabis use and the relationship between cannabis use and schizophrenia symptoms." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95187.

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Cannabis use increases the risk for psychosis with a dose response relationship; the risk is particularly strong before age 15. Factors precipitating use and explaining total amount used in patients are unknown. It is likewise unknown whether patients and controls differ on predictor profiles. The amount of variance in psychotic symptoms explained by premorbid cannabis use and the unique contribution of cannabis use when controlling for risk factors for schizophrenia is also unknown. The results show that some risk factors found in the community apply to both groups in the same way, and others did not. Total amount, intensity and duration of marijuana use were also associated with positive symptoms in patients. No mediation effects of marijuana use variables on more distal predictors of schizophrenia symptoms were found. Results are discussed in the context of a hypothesis of common neural networks for both schizophrenia and substance misuse.
L'usage de cannabis accroit proportionnellement le risque de développer la psychose. Ce risque est particulièrement élevé chez les moins de 15 ans. Les facteurs prédisposant à l'usage prémorbide, et expliquant le montant utilisé par les patients sont inexplorés, conséquemment, on ignore si ces groupes ont des prédispositions différentes. La variation dans les symptômes expliquée par ces facteurs d'usage et la contribution unique du cannabis, lorsque les facteurs de risques pour la psychose sont contrôlés, sont également inconnus. Les résultats démontrent que certains facteurs de risque s'appliquent aux deux populations et d'autres pas. Le montant, l'intensité et la durée de l'usage sont associés avec les symptômes positifs chez les patients. Aucun effet de médiation de l'usage de marijuana sur les facteurs de prédisposition à la schizophrénie n'a été observé. Les résultats sont examinés dans le contexte d'une hypothèse de réseaux neuronaux communs à la schizophrénie et l'usage de cannabis.
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McCabe, Patrick J. "Cannabis Use and Bipolar Disorder: Bipolar Disorder Case Identification and Cannabis Use Risk Assessment: A Dissertation." eScholarship@UMMS, 2011. https://escholarship.umassmed.edu/gsbs_diss/584.

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Bipolar disorders (BD) are characterized by symptoms of grandiosity, decreased need for sleep, pressure to keep talking, flight of ideas, distractibility, increased goal-directed activities, psychomotor agitation, and excessive involvement in pleasurable activities. Those with a bipolar disorder have a high degree of psychiatric comorbidity including substance use disorders, and they also experience increased mortality. Despite the widespread recognition of BD as an important psychiatric condition, available population-based estimates for BD prevalence differs across data sources. Cannabis is one of the most widely-used illicit substances. Evidence supports it as a risk factor for psychotic symptoms and disorders. Because populations with psychotic disorders and populations with bipolar disorder share genetic characteristics, cannabis may increase risk for bipolar disorders through the same pathways as it does with psychotic disorders. Limited and conflicting evidence regarding the association of cannabis use and bipolar disorder is currently available. This dissertation investigates cannabis use as a risk factor for incident manic symptoms and bipolar disorders in a large nationally representative longitudinal cohort. The first aim of this dissertation is to evaluate the implications for manic, hypomanic and major depressive episode prevalence estimates arising from the different approaches to assessing DSM-IV criterion between two national surveys. Differences in the assessment of impairment strongly influence manic or hypomanic classification within the NESARC. Compared to multiple imputation estimates (19.7% [95% CI: 19.3-20.1]) which treat depressed mood and anhedonia as separate symptoms, symptom assessment in the NESARC substantially underestimates major depressive episode prevalence (16.9% [95% CI: 16.1-17.6]). The second research objective examined self-reported cannabis use as a risk factor for incident manic symptoms, bipolar spectrum disorders (including manic and hypomanic episodes) and SCID-based recalibrated BD I and II. Cannabis use risk was assessed in the population as a whole and in sub-populations defined by age, substance abuse/dependence status, and family history. Among those reporting no lifetime major depressive or manic symptoms at baseline, self-reported past-year cannabis use was associated with increased odds of an incident week of extremely elevated or irritable mood accompanied by at least two manic episode criterion B symptoms (adj. OR 1.69, 95% CI: 1.08-2.65, p=.02) over the three year follow-up period. Among adults (ages 26 to 45) >=1 reported use(s) of cannabis per week was associated with incident manic or hypomanic episodes (adjusted OR 2.52, 95% CI: 1.32-4.80, p=.006). Among those endorsing no major depressive symptoms, substance abuse/dependence, or anti-social traits in their first degree relatives, past year cannabis use is associated with increased risk for incident bipolar spectrum disorders (adjusted OR 2.27, 95% CI: 1.01-5.10, p=.05) and CIDI recalibrated BD I and II (adjusted OR 5.49, 95% CI: 1.38-21.9, p=.02). Past year cannabis use risk for DSM-IV manic or hypomanic episodes among those aged 26 to 45 is concentrated in those with a baseline history of a substance use disorder (adj. OR 2.00, 95% CI: 1.10-3.66, p=.02) as compared to those with no such history (adj. OR 1.87, 95% CI: 0.49-7.21, p=.36). The third research objective of this dissertation was a sensitivity analysis using externally-predicted categorized exposures and continuous cannabis use propensities. The sensitivity analysis found evidence of exposure misclassification. Exposures defined by external propensity scores had improved cross-sectional association with bipolar spectrum disorders compared to reported use when both were compared to an external standard. No significant risk estimates were found for categorized predicted cannabis use among groups that were previously found to have significant risk from reported exposure. However, among adults 18 to 45 years of age with no manic or major depressive symptoms at baseline, past year cannabis use propensity (as a log transformed continuous measure) was associated with incident manic or hypomanic episodes (adj. OR 1.49, 95% CI: 1.10-2.03, p=.01). Elevated risk for high cannabis use propensity (>=1 use/week in the past year) was also found in this same group (adj. OR 1.33, 95% CI: 1.03-1.72, p=.03). Among those with no reported history of depression, substance abuse/dependence, or anti-social traits among their first-degree relatives, propensity for past year cannabis use (adj. OR 1.61, 95% CI: 1.11-2.32, p=.01) and propensity for >=1 use/week of cannabis in the past year (adj. OR 1.38, 95% CI: 1.03-1.85, p=.03) were associated with incident manic or hypomanic episodes. Among those without a substance use history at baseline, propensity for past year cannabis use (adj. OR 1.63, 95% CI: 1.33-1.55, p=1 use/week of cannabis in the past year (adj. OR 1.54, 95% CI: 1.26-1.88, p The findings of the first aim support the conclusion that the AUDADIS substantially under-estimated lifetime major depressive episode prevalence compared to an imputed estimate that treated anhedonia and depressed mood as separate and concurrent MDE symptoms. The operationalization of impairment for manic disorders in both the AUDADIS and CIDI strongly influences case identification, with the CIDI having suppressed manic and hypomanic prevalence estimates. Evidence was found supporting the conclusion that self-reported cannabis use is a significant risk factor for incident bipolar spectrum outcomes within subpopulations in a nationally representative cohort. A sensitivity analysis finds evidence that supports the conclusion that increasing cannabis use propensity is associated with increased risk of bipolar spectrum outcomes within population subgroups, with the greatest increased risk among those with the lowest innate risk. Under-reporting of illicit substance use is a major limitation in this dissertation; further study is needed with improved exposure measures.
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4

Schulz-Katterbach, Michèle Sabrina. "Cannabis and caries - does regular cannabis use increase the risk of caries in cigarette smokers? /." [S.l.] : [s.n.], 2009. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000297946.

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5

Kosty, Derek. "Trajectories of Cannabis Use Disorder: Risk and Developmental Factors, Clinical Characteristics, and Outcomes." Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/19200.

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Efforts to objectively inform cannabis discourses include research on the epidemiology of cannabis abuse and dependence disorders or, collectively, cannabis use disorder (CUD). For my dissertation I identified classes of individuals based on intraindividual CUD trajectory patterns and contrasted trajectory classes with respect to clinical characteristics of CUD, developmental risk factors, and psychosocial outcomes. Identifying differences between trajectory classes provides evidence for the validity of trajectory-based CUD constructs and informs the development of comprehensive models of CUD epidemiology and trajectory-specific intervention approaches. My dissertation used data from the Oregon Adolescent Depression Project, a prospective epidemiological study of the psychiatric and psychosocial functioning of a representative community-based sample randomly selected from nine high schools across western Oregon. Four waves of data collection occurred between mid-adolescence and early adulthood and included diagnostic interviews and self-report questionnaires. Onset and offset ages of all CUD episodes were recorded. The reference sample included 816 participants who completed all diagnostic interviews. A series of latent class growth models revealed three distinct CUD trajectory classes through age 30: (1) a persistent increasing risk class; (2) a maturing out class, marked by increasing risk through age 20 and then a decreasing risk through early adulthood; and (3) a stable low risk class. Rates of cannabis dependence were similar across the persistent increasing and the maturing out classes. Trajectory classes characterized by a history of CUD were associated with a variety of childhood risk factors and measures of psychosocial functioning during early adulthood. Participants who were male, had externalizing disorders, and had psychotic experiences during early adulthood discriminated between the persistent increasing and the maturing out classes. Future research based on more diverse samples is indicated, as are well-controlled tests of associations between risk factors, trajectory class membership, and psychosocial outcomes. A better understanding of these relationships will inform etiological theories of CUD and the development of effective intervention programs that target problematic cannabis use at specific developmental stages. Designing targeted versus undifferentiated interventions for those at greatest risk for adult psychosocial impairment could be a cost-effective way to mitigate the consequences of CUD.
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Cassidy, Clifford Mills. "Investigating common risk factors in the comorbidity of cannabis use and psychosis." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119360.

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Background. The comorbidity between psychotic illness and substance abuse is associated with negative outcomes. To better treat substance use in psychosis it is necessary to identify factors specifically promoting substance use in this population, particularly aspects of psychotic illness which may exacerbate substance use. Purpose. to identify whether early-life inattention-hyperactivity and deficits in reward processing could qualify as common factors underlying the comorbidity of psychotic illness and cannabis abuse. Methods. We conducted the following four experiments: 1. The ability of childhood symptoms of ADHD measured using retrospective parental report (Child Behavior Checklist) to predict cannabis-use outcomes in first episode psychosis (FEP). 2. Associations between self-reported anticipatory pleasure and cannabis use in psychosis patients and controls. 3. The effect of cannabis on daily activities and functional measures and on behavioural exertion for rewarding stimuli in psychosis patients and controls with cannabis use. 4. Examining physiological response to pleasant and cannabis images using event-related potentials (ERP), facial expressivity, and galvanic skin response in controls and psychosis patients with cannabis use. Results. 1. Higher levels of inattention symptoms in childhood predicted lifetime cannabis-use disorder and inability to maintain abstinence from cannabis in FEP. 2-4. Psychosis patients showed reward deficits on several measures including: self-reported reward response, engagement in effortful daily activities, behavioural exertion to seek pleasant stimuli, and sustained processing of pleasant stimuli as measured with the late positive potential (LPP) of the ERP. When comparing subjects' response to pleasant stimuli versus cannabis stimuli, control cannabis users showed a significant bias towards pleasant images on all measures, whereas patients showed similar response to both pleasant and cannabis stimuli on most measures. Reduced response on several of the measures on which patients showed a deficit was associated with greater cannabis use: self-reported reward response, behavioral exertion to seek pleasant stimuli, and LPP response to pleasant stimuli. Conclusions and significance. 1. Our finding that childhood inattention is associated with subsequent cannabis in FEP when complemented by studies showing these symptoms are more prevalent in subjects who later develop psychotic disorders is consistent with childhood inattention being a marker for shared vulnerability to develop both psychotic and substance-use disorders. 2-4. Deficits in reward processing are present in individuals with psychotic disorders and some of these deficits may predispose individuals to use cannabis more heavily. If these findings are further developed they could inform treatments targeted for substance use in populations with psychosis.
Introduction. La comorbidité entre les troubles psychotiques et l'abus de substances est associée à une évolution négative. Pour mieux traiter l'abus de substance dans la psychose, il est nécessaire d'identifier les facteurs spécifiques qui augmentent la prévalence de consommation de substances dans cette population, particulièrement les aspects du trouble psychotique qui pourraient exacerber la consommation de substances. Objectifs. Identifier si des symptômes d'hyperactivité-inattention durant l'enfance et des déficits dans les processus de récompense pourraient se qualifier comme des facteurs communs sous-jacents de la comorbidité des troubles psychotiques et de la consommation du cannabis. Méthodes. Nous avons fait les quatre expériences suivantes : 1. L'utilisation des symptômes de TDAH mesurés de façon rétrospective en utilisant un rapport des parents (Child Behavior Checklist) pour prédire la consommation de cannabis chez les premiers épisodes psychotiques (PEP). 2. L'association entre le plaisir anticipé rapporté et la consommation de cannabis chez les patients psychotiques et les contrôles. 3. L'examen de la réponse physiologique à des images plaisantes et de cannabis en utilisant les potentiels évoqués cérébraux (ERP), l'expressivité faciale et la conductivité de la peau chez les contrôles et les patients psychotiques qui consomment du cannabis. 4. L'effet du cannabis sur les activités quotidiennes, les mesures fonctionnelles et l'effortcomportemental pour des stimuli de récompense chez les patients psychotiques et les contrôles qui consomment du cannabis. Résultats. 1. Plus de symptômes d'inattention durant l'enfance prédirait un trouble de consommation du cannabis et l'inaptitude de rester abstinent pour le cannabis chez les PEP. 2-4. Les patients psychotiques démontrent des déficits de récompense sur plusieurs mesures incluant : la réponse rapportée de récompense, l'engagement dans des activités quotidiennes qui demandent de l'effort, l'effort exercé pour rechercher des stimuli plaisants et le traitement prolongé des stimuli plaisants tel que mesuré avec le potentiel retardé positif (LPP) de l'ERP. Lorsque l'on compare la réponse des sujets pour les stimuli plaisants versus les stimuli de cannabis, les consommateurs de cannabis contrôles ont démontré un biais significatif envers les images plaisantes sur toutes les mesures, alors que les patients ont démontré une réponse similaire sur les stimuli plaisants et de cannabis sur la plupart des mesures. Une réponse diminuée sur plusieurs mesures sur lesquelles les patients ont démontré un déficit était associée avec une consommation plus grande de cannabis : la réponse rapportée de récompense, l'effort comportemental pour rechercher des stimuli plaisants et la réponse LPP aux stimuli plaisants.Conclusions et signification. 1. Nos résultats concernant l'inattention durant l'enfance associée à une consommation subséquente du cannabis chez les PEP, lorsque complémentés par les études qui démontrent que ces symptômes sont plus prévalent chez les sujets qui développent plus tard des troubles psychotiques, sont consistants avec les symptômes d'inattention durant l'enfance qui sont déterminants dans la vulnérabilité à développer des troubles psychotiques et de consommation de substances. 2-4. Des déficits dans les processus de récompense sont présents chez les individus avec des troubles psychotiques et certains de ces déficits pourraient prédisposer les individus à consommer du cannabis de façon plus importante. Si ces résultats sont plus amplement développés, ils pourront donner des pistes de traitement pour la consommation de substances dans les populations psychotiques.
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Zimmermann, Petra, Hans-Ulrich Wittchen, Florian Waszak, Agnes Nocon, Michael Höfler, and Roselind Lieb. "Pathways into ecstasy use: The role of prior cannabis use and ecstasy availability." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-110187.

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Aim: To explore the role of cannabis use for the availability of ecstasy as a potential pathway to subsequent first ecstasy use. Methods: Baseline and 4-year follow-up data from a prospective-longitudinal community study of originally 3021 adolescents and young adults aged 14–24 years at baseline were assessed using the standardized M-CIDI and DSM-IV criteria. Results: Baseline cannabis users reported at follow-up more frequent access to ecstasy than cannabis non-users. Higher cannabis use frequencies were associated with increased ecstasy availability reports. Logistic regression analyses revealed that cannabis use and availability of ecstasy at baseline are predictors for incident ecstasy use during the follow-up period. Testing simultaneously the impact of prior cannabis use and ecstasy availability including potential confounders, the association with cannabis use and later ecstasy use was confirmed (OR = 6.3; 95% CI = 3.6–10.9). However, the association with ecstasy availability was no longer significant (OR = 1.2; 95% CI = 0.3–3.9). Conclusions: Results suggest that cannabis use is a powerful risk factor for subsequent first onset of ecstasy use and this relation cannot be sufficiently explained by availability of ecstasy in the observation period.
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Zimmermann, Petra, Hans-Ulrich Wittchen, Florian Waszak, Agnes Nocon, Michael Höfler, and Roselind Lieb. "Pathways into ecstasy use: The role of prior cannabis use and ecstasy availability." Technische Universität Dresden, 2005. https://tud.qucosa.de/id/qucosa%3A26818.

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Aim: To explore the role of cannabis use for the availability of ecstasy as a potential pathway to subsequent first ecstasy use. Methods: Baseline and 4-year follow-up data from a prospective-longitudinal community study of originally 3021 adolescents and young adults aged 14–24 years at baseline were assessed using the standardized M-CIDI and DSM-IV criteria. Results: Baseline cannabis users reported at follow-up more frequent access to ecstasy than cannabis non-users. Higher cannabis use frequencies were associated with increased ecstasy availability reports. Logistic regression analyses revealed that cannabis use and availability of ecstasy at baseline are predictors for incident ecstasy use during the follow-up period. Testing simultaneously the impact of prior cannabis use and ecstasy availability including potential confounders, the association with cannabis use and later ecstasy use was confirmed (OR = 6.3; 95% CI = 3.6–10.9). However, the association with ecstasy availability was no longer significant (OR = 1.2; 95% CI = 0.3–3.9). Conclusions: Results suggest that cannabis use is a powerful risk factor for subsequent first onset of ecstasy use and this relation cannot be sufficiently explained by availability of ecstasy in the observation period.
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Zammit, Stanley. "An investigation into the use of cannabis and tobacco as risk factors for schizophrenia." Thesis, Cardiff University, 2004. http://orca.cf.ac.uk/48919/.

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Schoeler, Tabea. "Continued cannabis use and risk of relapse in patients with a first episode psychosis." Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/continued-cannabis-use-and-risk-of-relapse-in-patients-with-a-first-episode-psychosis(5d17bfaf-a5fd-4ab9-a2f9-e2b44c9b9067).html.

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Although cannabis use following a first episode of psychosis (FEP) has been linked to poor outcome such as relapse, current understanding is limited regarding the nature of this association. To shed light on the nature of this relationship, this thesis employed multiple methodological approaches: First, I pooled together data from previous studies in order to estimate the cross-sectional effects of continued and discontinued cannabis use following the onset of psychosis and risk of relapse, using a meta-analytic design (Paper 1). Second, I prospectively collected follow up data from a cohort of patients presenting with a first episode psychosis to psychiatric services in south London. Paper 2 examined the magnitude of effect of continued cannabis use on risk of relapse and related outcomes by grouping patients into classes of different patterns of cannabis use following onset of psychosis. In Paper 3, longitudinal modelling was employed to further examine whether the link between continued cannabis use and risk of relapse persists when non-causal explanations for the association are taken into account (reverse causation, premorbid genetic confounding). My findings indicate that that former regular users who stopped using cannabis after the onset had the most favourable illness course with regard to relapse. The most unfavourable course was present in those who continued to use high-potency cannabis in a high frequency manner. The results also suggest that this association reflects a dose-dependent association that is unlikely to be a result of reverse causation (e.g. selfmedication) or genetic and environmental (e.g. other illicit drug use, medication nonadherence) confounding. These findings point to reductions in cannabis use as a crucial interventional target to reduce risk of relapse in patients with a first episode psychosis.
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Kuepper, Rebecca, Cécile Henquet, Roselind Lieb, Hans-Ulrich Wittchen, and Os Jim van. "Non-replication of interaction between cannabis use and trauma in predicting psychosis." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-129494.

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Cannabis use is considered a component cause of psychotic disorder interacting with genetic and environmental risk factors in increasing psychosis risk (Henquet et al., 2008). Recently, two cross-sectional and one prospective study provided evidence that cannabis use interacts additively with trauma to increase psychosis risk (Houston et al., 2008, Harley et al., 2010 and Konings et al., 2011). In an attempt at further replication, we examined prospective data from the German Early Developmental Stages of Psychopathology (EDSP) study (Wittchen et al., 1998b and Lieb et al., 2000).
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Kuepper, Rebecca, Cécile Henquet, Roselind Lieb, Hans-Ulrich Wittchen, and Os Jim van. "Non-replication of interaction between cannabis use and trauma in predicting psychosis." Technische Universität Dresden, 2011. https://tud.qucosa.de/id/qucosa%3A27330.

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Cannabis use is considered a component cause of psychotic disorder interacting with genetic and environmental risk factors in increasing psychosis risk (Henquet et al., 2008). Recently, two cross-sectional and one prospective study provided evidence that cannabis use interacts additively with trauma to increase psychosis risk (Houston et al., 2008, Harley et al., 2010 and Konings et al., 2011). In an attempt at further replication, we examined prospective data from the German Early Developmental Stages of Psychopathology (EDSP) study (Wittchen et al., 1998b and Lieb et al., 2000).
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Kuepper, Rebecca, Os Jim van, Roselind Lieb, Hans-Ulrich Wittchen, Michael Höfler, and Cécile Henquet. "Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-120779.

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Objective: To determine whether use of cannabis in adolescence increases the risk for psychotic outcomes by affecting the incidence and persistence of subclinical expression of psychosis in the general population (that is, expression of psychosis below the level required for a clinical diagnosis). Design: Analysis of data from a prospective population based cohort study in Germany (early developmental stages of psychopathology study). Setting: Population based cohort study in Germany. Participants: 1923 individuals from the general population, aged 14-24 at baseline. Main outcome measure: Incidence and persistence of subthreshold psychotic symptoms after use of cannabis in adolescence. Cannabis use and psychotic symptoms were assessed at three time points (baseline, T2 (3.5 years), T3 (8.4 years)) over a 10 year follow-up period with the Munich version of the composite international diagnostic interview (M-CIDI). Results: In individuals who had no reported lifetime psychotic symptoms and no reported lifetime cannabis use at baseline, incident cannabis use over the period from baseline to T2 increased the risk of later incident psychotic symptoms over the period from T2 to T3 (adjusted odds ratio 1.9, 95% confidence interval 1.1 to 3.1; P=0.021). Furthermore, continued use of cannabis increased the risk of persistent psychotic symptoms over the period from T2 to T3 (2.2, 1.2 to 4.2; P=0.016). The incidence rate of psychotic symptoms over the period from baseline to T2 was 31% (152) in exposed individuals versus 20% (284) in non-exposed individuals; over the period from T2 to T3 these rates were 14% (108) and 8% (49), respectively. Conclusion: Cannabis use is a risk factor for the development of incident psychotic symptoms. Continued cannabis use might increase the risk for psychotic disorder by impacting on the persistence of symptoms.
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Wiklund, Sofia, and Malin Frykstrand. "Hur kan ungdomar tycka att cannabis är farligt? : En studie om vad som påverkar ungdomars riskperception avseende cannabisbruk." Thesis, Södertörns högskola, Institutionen för samhällsvetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-26012.

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Andelen ungdomar som inte uppfattar några större risker med cannabisbruk har ökat de senaste åren. Ungdomarnas uppfattning av riskerna med cannabisbruk påverkar huruvida de kommer att välja att avstå från eller bruka drogen. Syftet med denna uppsats har varit att se vilka risk- och skyddsfaktorer som påverkar ungdomars riskperception avseende cannabisbruk. Frågeställningarna har varit hur föräldrarna, skolan och vännerna påverkar riskperceptionen. Uppsatsen utgår från en subjektiv syn på riskperception som innebär att inte en faktor ensamt kan förklara om ungdomarna har en låg eller hög riskperception. För att analysera resultatet i uppsatsen har risk- och skyddsfaktorer, som har setts minska eller öka sannolikheten för ett cannabisbruk, använts. Det material som ligger till grund för uppsatsens undersökning är Centralförbundet för alkohol och narkotikas drogvaneundersökning från år 2010. Resultatet har tagits fram med hjälp av logistiska regressionsanalyser vilka visar hur starkt olika faktorer relateras till en låg riskperception även när hänsyn tas till andra faktorer. Flera faktorer kopplade till vännerna och föräldrarna har i resultatet visat sig ha ett statistiskt samband med ungdomarnas riskperception avseende cannabisbruk. Samtidigt fanns inget samband mellan skolan och riskperceptionen när föräldrarna och vänner togs med i beaktande.
The proportion of young people who do not perceive any major risks with cannabis use has increased in recent years. Adolescents' perception of the risks affects whether they will choose to use cannabis or not. The purpose of this essay has been to analyze risk and protective factors that influence young people's risk perception regarding cannabis use. The main questions have been how parents, school and friends affect risk perception. The essay is based on a subjective view of risk perception, which means that not a single factor alone can explain why the adolescent has a low or high risk perception. Risk and protective factors that have been observed to decrease or increase the likelihood of cannabis use have been used to analyze the result. The material that has been used in this essay is a survey conducted by the Centralförbundet för alkohol och narkotika year 2010 among Swedish teenagers. The result has been established by using logistic regression analyzes which shows how strongly different factors are related to a low risk perception even when other factors are taken into account. Several factors linked to friends and parents have proved to have a statistically association with adolescents risk perception regarding cannabis use, this while the school doesn’t.
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Kuepper, Rebecca, Os Jim van, Roselind Lieb, Hans-Ulrich Wittchen, Michael Höfler, and Cécile Henquet. "Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study." Technische Universität Dresden, 2011. https://tud.qucosa.de/id/qucosa%3A27121.

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Objective: To determine whether use of cannabis in adolescence increases the risk for psychotic outcomes by affecting the incidence and persistence of subclinical expression of psychosis in the general population (that is, expression of psychosis below the level required for a clinical diagnosis). Design: Analysis of data from a prospective population based cohort study in Germany (early developmental stages of psychopathology study). Setting: Population based cohort study in Germany. Participants: 1923 individuals from the general population, aged 14-24 at baseline. Main outcome measure: Incidence and persistence of subthreshold psychotic symptoms after use of cannabis in adolescence. Cannabis use and psychotic symptoms were assessed at three time points (baseline, T2 (3.5 years), T3 (8.4 years)) over a 10 year follow-up period with the Munich version of the composite international diagnostic interview (M-CIDI). Results: In individuals who had no reported lifetime psychotic symptoms and no reported lifetime cannabis use at baseline, incident cannabis use over the period from baseline to T2 increased the risk of later incident psychotic symptoms over the period from T2 to T3 (adjusted odds ratio 1.9, 95% confidence interval 1.1 to 3.1; P=0.021). Furthermore, continued use of cannabis increased the risk of persistent psychotic symptoms over the period from T2 to T3 (2.2, 1.2 to 4.2; P=0.016). The incidence rate of psychotic symptoms over the period from baseline to T2 was 31% (152) in exposed individuals versus 20% (284) in non-exposed individuals; over the period from T2 to T3 these rates were 14% (108) and 8% (49), respectively. Conclusion: Cannabis use is a risk factor for the development of incident psychotic symptoms. Continued cannabis use might increase the risk for psychotic disorder by impacting on the persistence of symptoms.
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McPartling, Idara Sylvanus. "Self-Reported Health Status, Perceived Risk for Developing Breast Cancer, and Mammography Screening Use." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3182.

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Breast cancer is a widespread public health issue in the United States which affects all women. Although mammography is a proven screening tool, screening rates vary widely. Self-reported health status may play a role in how women perceive their risks for developing breast cancer, which may affect mammography use. The purpose of this cross-sectional survey study was to assess the association between self-reported health status and perceived risk for developing breast cancer, as well as perceived barriers towards mammography screening and use. Social action theory, which holds that social and the psychological factors influence health behaviors, served as the theoretical foundation of the study. A convenience sample of 309 African American, non-Hispanic White, and Hispanic women, aged 30+, was recruited to participate in the study. Linear and logistic regression analyses revealed the model including all variables were significance between self-reported health status, demographic characteristics, and the dependent variables perceived risk of breast cancer, receipt of a mammogram in the last 2 years, and barriers (personal, economic, and health). However, self-reported health status was not a significant individual predictor in any of the analyses, and the null hypotheses for the research questions were not rejected. This study may promote positive social change by providing information on the necessity of interdisciplinary and interrelated educational and intervention approaches to address the challenges of women from diverse populations receiving regular mammograms.
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O'Neill, Christina. "Recreational drug use : a risky business : an ethnographic account of perceived and experienced risk." Thesis, Queen's University Belfast, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602780.

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Much of the existing literature on drug related risk focuses on problem drug use, placing emphasis on the range of health, legal and social harms which are often associated with such behaviour. The present study investigates perceptions and experiences of risk among a sample of self-reported "recreational" drug users in Northern Ireland. The overall aim of the research was to gain insight into the lived experience of recreational drug users, paying particular attention to risk perception and risk behaviour, as well as the myriad of environmental forces which interact to reduce or reproduce drug related risk. At a theoretical level, the study examines Rhodes' Risk Environment approach (2002, 2009; Rhodes et al., 2003) in the context of recreational patterns of drug use. To date, Rhodes' framework has been limited to studies of risk associated with problem drug misuse, Le., injecting drug use. The research utilised an ethnographic approach and findings draw on data from more than 60 in-depth interviews and approximately 70 observation sessions recorded between 2007 and 2012. A total of 45 self-reported recreational drug users, aged 18 years or more, participated in at least one of four research phases. The final phase of the research included respondents from rural (n=20) and urban (n=15) areas in Northern Ireland. Key findings highlight the role of environmental forces at micro, meso and macro-levels, in shaping risk perception and risk behaviour. These forces interact to reduce or reproduce drug related harm. Three types of risk were identified in relation to recreational patterns of drug consumption: health risk, legal risk and social risk. The study discusses these risks and the strategies that respondents adopt t9 manage risk. Findings demonstrate the subjective nature of risk perception and highlight significant disparities between lay and expert discourses on drug related risk. The thesis concludes with a discussion of implications for drug research and policy.
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Fabayo, Oluwayomi. "Perceived Cardiovascular Risk Among West Africa Immigrants in DeKalb County, Georgia." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5328.

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West African immigrants appear to carry a heavier burden of hypertensive heart disease than the native-born African Americans in the United States. In this study, I used the socioecological model theory as a guide to examine the association between perceived stress, length of stay in United States, smoking status, housing conditions, and the risk of hypertensive heart disease among West African immigrants, ages 18 - 54 years in DeKalb County, Georgia. In this quantitative, cross-sectional design, self-reported data were collected from a sample of West African immigrant (N=107) in the DeKalb County of Georgia, using a demographic data/screening sheet and the Perceived Stress Scale. Multivariate logistic regression analysis was used to determine the association between hypertensive heart disease and perceived stress, smoking status, length of stay in the United States, and housing condition, having adjusted for the modifying variables age and education. Results indicated that length of stay in the United States [p =.019, Phi =.331], housing condition [p=.156, R2 =.019], smoking status [p=.050, R2 =.036] and experienced perceived stress experienced [p=.312, R2=.010] are associated with risk of developing hypertensive heart disease. There was a statistically significant association between age [p=.002] and the development of hypertensive heart disease. The result of this study can contribute to positive social change by helping public health agencies to target some of the identified risk factors for hypertensive heart disease in foreign born African American population so as to mitigate the adverse health outcomes associated with hypertensive heart disease.
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19

Mustonen, A. (Antti). "Adolescent substance use and risk of psychosis in the Northern Finland Birth Cohort 1986." Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526220314.

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Abstract The aim of this study was to investigate the association between adolescent substance use and psychosis in later life, after taking into account a wide range of known confounders, using data from the Northern Finland Birth Cohort 1986 (N = 9432). Adolescence is a vulnerable neurodevelopmental period, during which many brain maturation processes take place. Substance use during this critical period may disrupt these processes, ultimately leading to mental health problems. Several meta-analyses have demonstrated associations between cannabis use and tobacco smoking and increased risk of psychotic disorders. However, lack of data on the temporal order of the association and uncertainty in relation to the role of confounding factors warranted further studies. Furthermore, there are no longitudinal studies on the association between adolescent inhalant use and psychotic disorders. The study sample consisted of the Northern Finland Birth Cohort 1986. There were 7344 adolescents who participated in the follow-up study in 2001-2002, when they were aged 15-16 years. Adolescents who answered the questions on substance use and psychotic experiences (PROD-screen) were included in the present study. The final sample included 6542 subjects. In this study, an increased risk of psychosis was found in those subjects who had used cannabis five times or more, smoked 10 or more cigarettes daily or had used inhalants 2-4 times or more. Each of these substances were associated with psychosis in a dose-response manner, even after adjustments for confounders. In addition, initiation of daily smoking at 13 years of age or earlier was associated with increased risk of psychosis compared to later initiation. In this comprehensive longitudinal population-based study, frequent cannabis use, daily tobacco smoking and frequent inhalant use in adolescence were independently associated with increased risk of incident psychosis, even after adjusting for confounders such as baseline psychotic experiences, other substance use and history of parental psychosis and substance abuse disorder. The results supply yet another reason to implement effective prevention strategies
Tiivistelmä Väitöstutkimuksen tarkoituksena oli selvittää, onko teini-iän päihteidenkäytöllä yhteyttä psykoosiin sairastumiseen senkin jälkeen, kun sekoittavat tekijät on huomioitu. Aineistona käytettiin vuoden 1986 Pohjois- Suomen syntymäkohorttia (N = 9 432). Teini-iässä aivot muovautuvat ja kypsyvät nopeasti, minkä vuoksi se on erityisen herkkää aikaa päihteiden haitallisille vaikutuksille. Nuorena aloitettu päihteidenkäyttö saattaa häiritä aivojen kypsymistä, ja kehityksen häiriintyminen voi myöhemmin altistaa mielenterveysongelmille. Aiempien tutkimusten pohjalta tiedetään, että kannabiksen käyttö ja tupakointi ovat yhteydessä korkeampaan riskiin sairastua psykoosiin. Päihteidenkäytön ja psykoosiin sairastumisen välistä ajallista yhteyttä ei olla kuitenkaan aiemmin kyetty tutkimaan vakuuttavasti, eikä huomioon ole otettu nuoruuden aikaisia psykoottisia kokemuksia. Inhalanttien käytön eli imppaamisen yhteydestä psykoosiriskiin ei ole julkaistu yhtään pitkittäistutkimusta. Tutkimusaineisto koostui Pohjois-Suomen syntymäkohortista vuodelta 1986. Vuosina 2001–2002 järjestettyyn seurantatutkimukseen osallistui 7344 15–16- vuotiasta nuorta. Lopullisessa otoksessa (n=6542) huomioitiin henkilöt, jotka vastasivat kysymyksiin psykoottisista kokemuksista ja päihteidenkäytöstä. Kannabiksen käyttö 5 kertaa tai enemmän, päivittäinen tupakointi 10 savuketta tai enemmän ja inhalanttien käyttö 2-4 kertaa tai enemmän olivat yhteydessä korkeampaan riskiin sairastua psykoosiin seurannan aikana sekoittavien tekijöiden huomioimisenkin jälkeen. Tutkittujen päihteiden käyttö kasvatti psykoosiin sairastumisen riskiä päihteen käyttömäärän mukaan. Lisäksi päivittäisen tupakoinnin aloittaminen 13-vuotiaana tai aiemmin oli yhteydessä korkeampaan psykoosiriskiin tupakoinnin myöhemmin aloittaneisiin verrattuna. Tässä suuressa pitkittäisessä, yleisväestöön perustuvassa tutkimuksessa havaittiin, että toistuva kannabiksen käyttö, päivittäinen ja runsas tupakointi sekä toistuva inhalanttien käyttö teini-iässä olivat itsenäisesti yhteydessä kohonneeseen psykoosiriskiin, vaikka aiemmat psykoottiset kokemukset, muu päihdekäyttö, vanhempien psykoosisairaudet ja päihdeongelmat otettiin huomioon. Tulosten perusteella nuorten runsaan päihteidenkäytön ennaltaehkäisy on tärkeää ja sillä on todennäköisesti positiivisia vaikutuksia nuorten mielenterveyteen
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Roxanne, Henry. "The association between perceived parenting styles and adolescent substance use." Thesis, University of the Western Cape, 2010. http://hdl.handle.net/11394/2108.

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Magister Psychologiae - MPsych
Using the literature on Baumrind's theory of Parenting Styles and how perceptions of these are associated to adolescent at-risk behaviour, this study set out to examine whether any parenting style increased or decreased adolescent substance use. The central aim of this study was to examine the association between perceived parenting styles and adolescent substance use. To further this, 239 grade 10 and 11 adolescent participants were drawn from 3 schools in Mitchell's Plain, a suburb in the Western Cape (with permission granted from the Education Department). This particular suburb was chosen due to the high rates of substance use and substance related crime within the area. A quantitative research design was implemented within this study. The participants were required to complete the Drug Use Disorders Identification Test (DUDIT), a questionnaire aimed at measuring drug use, and the Parental Authority Questionnaire (PAQ), aimed at measuring perceived parenting styles and a Biographical Questionnaire to provide additional information. Informed consent was obtained and the confidentiality of the schools and participants were protected. Data analysis was conducted using SPSS, a data analysis programme available at the University of the Western Cape. Results show that substance use reduction was significantly related to a perceived authoritative parenting style. However, no significant relationships could be found between perceived permissive and authoritarian parenting style. Significant difference was found in the results obtained for male and female adolescents, with males generally appearing to use more substances. It can be concluded that perceived authoritative parenting styles have an important role to play in the prevention of adolescent substance abuse.
South Africa
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21

Winicour, Dawn Blake Catanzaro Salvatore J. "Outcome expectancies, best-friend use, perceived family support, and coping variables as predictors of substance use among at-risk adolescents." Normal, Ill. : Illinois State University, 2006. http://proquest.umi.com/pqdweb?index=0&did=1276398701&SrchMode=1&sid=10&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1181317255&clientId=43838.

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Thesis (Ph. D.)--Illinois State University, 2006.
Title from title page screen, viewed on June 8, 2007. Dissertation Committee: Salvatore Catanzaro (chair), Matthew Hesson-McInnis, Jeff Laurent, Adena Meyers, Mark Swerdlik. Includes bibliographical references (leaves 117-133) and abstract. Also available in print.
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22

Respress, Brandon Noelle. "Social Determinants of Adolescent Risk Behaviors: An Examination of Depressive Symptoms and Sexual Risk, Substance Use, and Suicide Risk Behaviors." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1270238396.

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23

Singh, Jay P. [Verfasser]. "International Perspectives on Forensic Risk Assessment : Measuring Use, Perceived Utility, and Research Quality / Jay P. Singh." Konstanz : Bibliothek der Universität Konstanz, 2016. http://d-nb.info/1112479643/34.

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24

Sydow, Kirsten von, Roselind Lieb, Hildegard Pfister, Michael Höfler, and Hans-Ulrich Wittchen. "What predicts incident use of cannabis and progression to abuse and dependence? A 4-year prospective examination of risk factors in a community sample of adolescents and young adults." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-109990.

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Objectives: To determine risk factors of incident onset of use, abuse and dependence of cannabis in a community sample of adolescents and young adults. Methods: Risk factors were examined in a prospective longitudinal design across 4 years in a representative sample (N=2446) aged 14-24 at the outset of the study (EDSP). Patterns of DSM-IV defined cannabis use, abuse and dependence were assessed with the Composite International Diagnostic Interview (M-CIDI). Potential risk factors were assessed at baseline. Incident cannabis use, abuse and dependence at second follow-up (on average 42 months after baseline) were the main outcome measures in this study. Associations were analyzed with logistic and negative binomial regressions. Results: Using 11 of a total of 56 variables examined, the predictive value of the final multiple logistic regression for incident cannabis use was moderately good (area under the ROC curve=0.78). Cannabis use frequency was predicted in the final model by 18 variables, cannabis abuse by two variables in the younger subsample and nine factors in the older group, and dependence by eight variables (dependence: ROC curve area=0.97). Incident cannabis use was predicted mainly by availability of drugs, peers’ drug use, a more ‘positive’ attitude towards future drug use, and regular previous use of licit drugs, while cannabis dependence was predicted primarily by parental death before age 15, deprived socio-economic status, and baseline use of other illicit drugs. Conclusion: Different factors predict the onset or severity of cannabis use and the progression to abuse and dependence. In addition to well-documented risk factors such as peer group pressure, drug availability, and low self-esteem, findings suggest that family history (e.g. parental mental disorders, early parental death), and prior experiences with legal drugs play a significant role in the initiation of cannabis consumption and the transition to cannabis use disorders in adolescents and young adults. Findings suggest that early intervention and prevention might be improved by better targeted treatment.
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25

Cano, Stefan, Christelle Chrea, Thomas Salzberger, Thomas Alfieri, Gerard Emilien, Nelly Mainy, Antonio Ramazzotti, Frank Lüdicke, and Rolf Weitkunat. "Development and validation of a new instrument to measure perceived risks associated with the use of tobacco and nicotine-containing products." BioMed Central, 2018. http://dx.doi.org/10.1186/s12955-018-0997-5.

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Making tobacco products associated with lower risks available to smokers who would otherwise continue smoking is recognized as an important strategy towards addressing smoking-related harm. Predicting use behavior is an important major component of product risk assessment. In this context, risk perception is a possible factor driving tobacco product uptake and use. As prior to market launch real-world actual product use cannot be observed, assessing risk perception can provide predictive information. Considering the lack of suitable validated self-report instruments, the development of a new instrument was undertaken to quantify perceived risks of tobacco and nicotine-containing products by adult smokers, former smokers and never-smokers. Initial items were constructed based on a literature review, focus groups and expert opinion. Data for scale formation and assessment were obtained through two successive US-based web surveys (n=2020 and 1640 completers, respectively). Psychometric evaluation was based on Rasch Measurement Theory and Classical Test Theory. Psychometric evaluation supported the formation of an 18-item Perceived Health Risk scale and a 7-item Perceived Addiction Risk scale: item response option thresholds were ordered correctly for all items; item locations in each scale were spread out (coverage range 75-87%); scale reliability was supported by high person separation indices > 0.93, Cronbach's alpha > 0.98 and Corrected Item-Total Correlations > 0.88; and no differential item functioning was present. Construct validity evaluations met expectations through inter-scale correlations and findings from known-group comparisons. The Perceived Risk Instrument is a psychometrically robust instrument applicable for general and personal risk perception measurement, for use in different types of products (including cigarettes, nicotine replacement therapy, potential Modified Risk Tobacco Products), and for different status groups (i.e., current smokers with and without intention to quit, former smokers, never smokers).
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26

PETEET, (MITCHELL) BRIDGETTE J. "GENDER AS A MODERATOR OF FAMILY DRUG INFLUENCE AND CHILD FUTURE DRUG RISK." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1112968034.

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27

Hollar, Madison K. "The Role of Perceived Risk, Peer Disapproval and Parental Involvement in Marijuana Use Among African American Youth." University of Cincinnati / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1623166854090286.

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28

Perez, Victor W. "The social production of risk perceived risk and disapproval as mechanisms of social control in a social influence model of youth marijuana use /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 339 p, 2007. http://proquest.umi.com/pqdweb?did=1362536101&sid=46&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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29

Sydow, Kirsten von, Roselind Lieb, Hildegard Pfister, Michael Höfler, and Hans-Ulrich Wittchen. "What predicts incident use of cannabis and progression to abuse and dependence? A 4-year prospective examination of risk factors in a community sample of adolescents and young adults." Technische Universität Dresden, 2002. https://tud.qucosa.de/id/qucosa%3A26804.

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Objectives: To determine risk factors of incident onset of use, abuse and dependence of cannabis in a community sample of adolescents and young adults. Methods: Risk factors were examined in a prospective longitudinal design across 4 years in a representative sample (N=2446) aged 14-24 at the outset of the study (EDSP). Patterns of DSM-IV defined cannabis use, abuse and dependence were assessed with the Composite International Diagnostic Interview (M-CIDI). Potential risk factors were assessed at baseline. Incident cannabis use, abuse and dependence at second follow-up (on average 42 months after baseline) were the main outcome measures in this study. Associations were analyzed with logistic and negative binomial regressions. Results: Using 11 of a total of 56 variables examined, the predictive value of the final multiple logistic regression for incident cannabis use was moderately good (area under the ROC curve=0.78). Cannabis use frequency was predicted in the final model by 18 variables, cannabis abuse by two variables in the younger subsample and nine factors in the older group, and dependence by eight variables (dependence: ROC curve area=0.97). Incident cannabis use was predicted mainly by availability of drugs, peers’ drug use, a more ‘positive’ attitude towards future drug use, and regular previous use of licit drugs, while cannabis dependence was predicted primarily by parental death before age 15, deprived socio-economic status, and baseline use of other illicit drugs. Conclusion: Different factors predict the onset or severity of cannabis use and the progression to abuse and dependence. In addition to well-documented risk factors such as peer group pressure, drug availability, and low self-esteem, findings suggest that family history (e.g. parental mental disorders, early parental death), and prior experiences with legal drugs play a significant role in the initiation of cannabis consumption and the transition to cannabis use disorders in adolescents and young adults. Findings suggest that early intervention and prevention might be improved by better targeted treatment.
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30

Johnson-Mallard, Versie. "The effects of an education/behavioral intervention on knowledge, perceived risk and self-efficacy in women." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001196.

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31

Rich, Edna Grace. "Exploring perceived reasons and risk factors for illicit drug use among youth in the Western Cape: implications for primary prevention." University of the Western Cape, 2017. http://hdl.handle.net/11394/6137.

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Philosophiae Doctor - PhD (Social Work)
Globally, drug abuse among youth is recognised as one of our greatest health and social problems and, as in other countries, South Africa is battling with this phenomenon. Drug abuse among youth (including children and adolescents) is on the increase, and a National Youth Risk Behaviour Survey, conducted at High Schools in South Africa, reveals that overall, almost 50% of grade 8-11 learners had used alcohol, and 13% had indulged in cannabis use in their lifetime. Drug abuse at an early age has been associated with various problems, such as risky sexual behaviours, health problems, depression, crime, and ultimately drug addiction, which often occur at a later age. A better understanding of the perceived reasons and the risk factors that influence adolescent drug use is crucial for the development of effective prevention strategies.
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32

Rich, Edna Grace. "Exploring perceived reasons ands risk factors for illicit drug use among youth in the Western Cape: Implications for primary prevention." University of the Western Cape, 2017. http://hdl.handle.net/11394/6081.

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Philosophiae Doctor - PhD (Social Work)
Globally, drug abuse among youth is recognised as one of our greatest health and social problems and, as in other countries, South Africa is battling with this phenomenon. Drug abuse among youth (including children and adolescents) is on the increase, and a National Youth Risk Behaviour Survey, conducted at High Schools in South Africa, reveals that overall, almost 50% of grade 8-11 learners had used alcohol, and 13% had indulged in cannabis use in their lifetime. Drug abuse at an early age has been associated with various problems, such as risky sexual behaviours, health problems, depression, crime, and ultimately drug addiction, which often occur at a later age. A better understanding of the perceived reasons and the risk factors that influence adolescent drug use is crucial for the development of effective prevention strategies.
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33

Malm, Lars, and Manne Sterner. "Att hitta fram till tillit : En studie av kartapplikationen i iPhone och användares tillit till denna." Thesis, Södertörns högskola, Institutionen för kommunikation, medier och it, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-15324.

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Trust is a concept used throughout our daily lives. We give trust to friends, colleagues and strangers. We also give trust to the technical artifacts we use in our everyday lives. We must also rely on the services we use to work the way we expect them to. There is plenty of research on trust in e-commerce and online banking on website based platforms. What is missing is research on how we give trust to mobile map applications (and mobile applications in general), and how this trust, or lack of trust, affect our use of map applications in everyday life. We will also use a model of trust to see if we can get a deeper understanding of this trust.
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34

Lovejoy, Jennette P. "Relationships among Media Use, Psychological States, and Health Behavior Intentions." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1289576474.

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35

Burbage, Michelle L. B. A. "Lifetime Heroin Use among Americans: An Exploration of Social Determinants." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491314797226285.

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36

Sundin, Elisabeth, and Sharon Stifanos. "Förtroende och FinTech : En studie om kunders upplevda förtroende fördigitala finansiella tjänster." Thesis, Södertörns högskola, Företagsekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-45785.

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During the last couple of years there has been a major digitalization of the financial sectorwhich FinTech have largely contributed to. FinTech does not solely contribute withpossibilities, but it also inflicts risks within the financial system when adding challengesrelated to IT-security. These risks pose new operational risks within the financial sector.Therefore, the purpose of this study is to examine as well as analyse different variables thatexplain the perceived trust and risks when using these digital financial services. This isbecause customers play a vital role in keeping their services as well as maintaining financialstability within the FinTech corporations. To examine the subject in this study a deductiveapproach is applied which focuses on previous empirical research and models likeTechnology Acceptance Model (TAM), Elaboration Likelihood Model (ELM) as well asBehavioral finance. These models aim to explain how customers accept new digitalphenomenon. Furthermore, the study performs a quantitative research method through a webbased survey questionnaire. The study examines the independent variables usage, perceivedability to adapt and perceived risk in relation to the dependent factor perceived trust. Thestudy’s sample consists of 185 survey responses which were analyzed through descriptive andinferential statistics. The hypotheses were tested using a multiple regression analysis wherethe independent variables and control variables were analyzed against the dependent variable.The empirical findings showed that customers' perceived ability to adapt to FinTech servicesdid not have a statistically significant effect on perceived trust. Furthermore, perceived riskand usage had a statistically proven influence on perceived trust. The control variables for thisstudy were age and gender where neither had a statistical association to the dependentvariable. Lastly, the empirical findings of the study can be useful for FinTech companiessince it proves that risks need to be minimized to increase perceived trust
Det har skett en stor digitalisering av den finansiella sektorn under de senaste åren därFinTech och dess tjänster har haft en betydande roll. Dock är inte de innovativa digitalatjänsterna som FinTech bidrar till enbart möjligheter, utan det utsätter även den finansiellasektorn för risker. På grund av digitaliseringen medför dessa risker nya operationella riskerinom den finansiella sektorn. Studiens syfte är därav att undersöka och analysera de variablersom förklarar det upplevda förtroendet och riskerna som finns vid användningen av digitalafinansiella tjänster. Studiens fokus ligger på kunderna då de har en nyckelroll i bevarandet avdessa tjänster. Studien har sin grund i ett deduktivt tillvägagångssätt med fokus på tidigareempirisk forskning på området, men även olika modeller som Technology Acceptance Model(TAM), Elaboration Likelihood Model (ELM) samt Behavioral finance som syftar till attförklara hur kunden accepterar nya digitala fenomen. För att undersöka detta tillämpas enkvantitativ metod genom användningen av en webbaserad surveyundersökning. Urvalet bestårav 185 svar som därefter analyserades genom deskriptiv statistik och inferentiell statistik.Detta skedde i form av en multipel regressionsanalys som analyserade studiens tre hypoteserdär studiens tre oberoende variabler och kontrollvariabler analyserades emot studiensberoende variabel. Resultaten visade på att risk och användning hade ett statistiskt sambandmed det upplevda förtroendet medan den egna upplevda förmågan inte hade det. Studiensresultat kan vara användbara för FinTech-företag då resultaten visar att risker måste minskasför att kundförtroendet ska öka.
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Kåhlman, Hanna, and Ardiana Selmani. "Cannabismissbruk - hur är detta relaterat till unga vuxnas övriga problem? : En jämförande studie utifrån ASI-data i Jönköpings län." Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för beteendevetenskap och socialt arbete, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-22565.

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Cannabis är den vanligaste illegala drogen bland unga vuxna i Sverige. Det är en omdebatterad drog, debatterna handlar ofta om huruvida cannabis effekter är negativa eller inte. Detta examensarbete undersöker om det finns skillnader i problemnivå inom olika livsområden beroende på grad av cannabisbruk. Examensarbetet är en kvantitativstudie som genom ett antal statistiska analyser jämför tre grupper av unga vuxna samt predicerar sannolikheten för vilka som löper störst risk att vara regelbundna cannabisanvändare. Resultatet tyder på att problemnivån ökar inom flera livsområden beroende på grad av cannabisbruk. Högre involvering i cannabisbruk är förknippat med högre problemnivå i psykisk hälsa, narkotikabruk, narkotikabrott samt hereditet för narkotika. Vidare visar resultatet att faktorer som att vara man, bo i storstad och hereditet för narkotika är riskfaktorer som kan predicera ett regelbundet cannabisbruk. Examensarbetets slutsatser ger stöd för att ökad cannabisinvolvering tycks medverka till missbruk av andra illegala droger och tycks ha negativ påverkanseffekt på psykisk hälsa samt att benägenhet till brottslighet snarare har att göra med selektion än med involvering i cannabisbruk.
Cannabis is the most commonly used illicit drug among young adults in Sweden. It is a controversial drug, the debates about cannabis are often about whether cannabis effects are negative or not. This thesis examines whether there are differences in the level of problems in different areas of life depending on the extent of cannabis use. The thesis is a quantitative study by a number of statistical analyzes comparing three groups of young adults, and predicts the probability of which ones are most likely to be regular cannabis users. The results suggest that in many areas of life the problem level is increasing, depending on the extent of cannabis use. Higher involvement in cannabis use is associated with problems of higher levels in mental health, drug use, drug and family history of narcotics. Furthermore, the results show that factors such as being male, living in a big city and family history of illicit drugs are risk factors that can predict a regular cannabis use. The findings of the thesis provide support for that increased cannabis involvement seems to contribute to the abuse of other illicit drugs and seem to have a negative impact on mental health, and at last that the tendency to commit crime has rather to do with personality factors than cannabis use.
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Martin, Rochelle Elizabeth. "Gender differences in HIV-related attitudes, knowledge, and perceived risk of infection among adolescents in day-treatment for substance use, and their effect on response to preventive intervention." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ58725.pdf.

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39

Li, Xiaolin. "An Empirical Examination of Factors Affecting Adoption of An Online Direct Sales Channel by Small and Medium-Sized Enterprises." Kent State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=kent1214531897.

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40

Koosha, Amirmohammad. "Understanding Adoption of Mobile Wallets : On Aged Population." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231107.

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A mobile wallet is a mobile application that is intended to replace leather wallets. With high mobile and Internet penetration and increased life expectancy in developed economies, adoption of mobile wallets by the older population is becoming more important due to new trends. Therefore, this thesis aims to understand and increase adoption of mobile wallets in developed economies by the citizens between the ages of 50 to 75. Based on the mobile payment technology acceptance model (MPTAM) and an extensive literature review, a simplified model is suggested. Three sub-questions (on 1 - social influence, 2 - perceived security, trust and risks, and 3 – perceived ease of use) are proposed for further study, which has been suggested in the literature to have more importance for the targeted demography. An exploratory qualitative study based on in-depth semi-structured interviews was conducted. The findings show that social influence can have direct or indirect effects. Moreover, several factors were identified that seems to have impacts on the degree to which a content can influence people. In addition, perceived trust, security, and risks seem to be the most important impediment for the adoption of mobile wallets, especially for risk-averse people. Furthermore, perceived ease of use can improve the values that mobile wallets may provide. Perceived ease of use is more important for the targeted age group since some of the potential users in this age group has reduced learning and physical abilities. Finally, many implications of the findings and methods to improve the adoption of mobile wallets for the selected demography, i.e. restriction and customization, use of familiar design, use of strong brands, etc. are suggested.
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Blume, Pontus, and Filip Ekberg. "Användbarhet vs Integritet : En fallstudie om hur användbarhet påverkar villighet att dela personlig information på Facebooks plattformar." Thesis, Uppsala universitet, Institutionen för informatik och media, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-447006.

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Increased participation in various social media platforms have led to large amounts of user data being generated, creating an opportunity for businesses that run the platforms to store and sell the data. This has created a situation where users are forced to weigh the benefits of using the platforms against sharing their personal information, which is a risk to their privacy. To address this issue, this study investigates how users weigh usability benefits against the perceived risks of sharing personal information. A case study was conducted on platforms run by Facebook (FP). Data collection was done through interviews and by gathering previous research before the result was analyzed using a qualitative method. The interview questions addressed usefulness, perceived risk and integrity management and were, among other research, formulated from the Technology Acceptance Model. The study made several interesting findings about usefulness, users’ need for integrity and how they perceive and tolerate various risks. Conclusions could then be drawn about how these findings affect users’ decision making process regarding their intention to use FP.
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42

Kavak, Welat, and Kalid Anwar. "Technological Innovation in Mobile Payment Solutions : A study on factors affecting the adoption rate of mobile payment solutions." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264116.

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The advent of mobile payment solution has brought a mixed reaction on the mind of potential consumers on whether to adopt or not. Also, the mobile payment has elicited discussion about its future. The major question is on whether the technology will replace traditional banking processes, or if it will act as a compliment. The thesis seeks to promote the adoption of mobile payment by improving available information for stakeholders. The advent of mobile payment technology shows that it has a high number of benefits, but it does not match with the current adoption rate. The statistics show that the majority of users of mobile payment uses it to for smaller transactions such as the purchase of books and food. The slow uptake of mobile payment adoption vis a vis immense benefit of the platform. The disparity motivated the study on factors that influence solution adoptions. The thesis provides a clear linkage of factors such as environmental risk, reputation, trust, perceived usefulness, ease of use and mobility in influencing potential consumer attitude and intention to use a specific payment solution.
Potentiella konsumenter av mobila betalningslösningar har gett en blandad reaktion på huruvida de ska ta sig an innovationen eller inte. De nya betalningslösningarna har även väckt diskussioner huruvida innovationen ska ersätta traditionella bankprocesser eller om de kommer komplettera varandra. Arbetet har i syfte att främja upptagande av mobila betalningar genom att förbättra tillgänglig information för intressenter. Det visar sig att mobila betalningar har större antal förmåner än traditionella betalningslösningar, dock speglar detta inte graden av användningen av teknologin. Statistiken visar att majoriteten av användare av mobila betalningar använder sig av teknologin för mindre transaktioner som exemplvis köp av böcker och mat. Faktorer som påverkar upptagandet av nya innovationer är framförallt säkerhetsrisk, rykte, förtroende, uppfattad användbarhet, uppfattad användarvänlighet samt flexibiliteten av betalningslösningen.
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Severe, Marie Sandra. "Association Between Childhood Sexual Abuse and HIV-Related Risk Factors for HIV-Positive Haitian Women." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2279.

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Childhood sexual abuse (CSA) is one of the least studied HIV-related risk factors in Haiti although research in the United States and Europe has clearly established the link between childhood trauma and HIV risk behaviors. Understanding the role and impact of CSA on HIV-positive Haitian women is likely to strengthen future HIV prevention and treatment efforts aimed at this vulnerable group. The current study was a cross-sectional examination of baseline data collected during a randomized trial of a cognitive-behavioral stress management (CBSM) intervention in Haiti. The purpose of this study was to analyze the association between CSA and sexual risk behaviors, alcohol use, and social support in a group of Haitian women, ages 17-55 (n=229), who are HIV-positive alcohol users living in Haiti. The outcomes investigated were the respondents’ level of exposure to CSA and their current HIV-related risk factors. The Theory of Gender and Power provided the theoretical framework for variable selection and associative exploration. Statistical tests included descriptive analyses, chi-square tests, analysis of variance (ANOVA), and correlations. Results showed that women who were exposed to some level of sexual abuse during childhood had less favorable attitudes towards condom use than women who reported no exposure to sexual abuse during childhood [F(2, 217) = 5.10, p = .007]. There were no differences between exposure groups for the remaining sexual risk behaviors: multiple partners, knowledge of HIV, and sexual self-efficacy. Women who were exposed to CSA also reported higher levels of alcohol use than reported by the women in the non-exposure group. Finally, there were no differences between exposure groups for social support. Group differences in attitudes towards condom use and levels of alcohol use among HIV-positive Haitian women demonstrate that HIV-positive individuals have different past and present experiences that affect their current beliefs and behaviors. Examining women at the beginning of their diagnosis for childhood trauma and providing targeted interventions for coping with that trauma presents a valuable research opportunity. The findings of the current study suggest that more research is required to understand the association between CSA and HIV-related risk factors in this subset of the HIV-positive population.
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Cabrejo, Pinto Daniel Fernando, and Carbonel Andrea Miki Romero. "Los riesgos percibidos de seguridad, privacidad y desempeño por el consumidor en relación con la adopción y uso de la banca online." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/653914.

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La presente investigación tiene como principal objetivo poder analizar los riesgos de la banca por internet y cómo afectan en el uso sobre el usuario del sector bancario peruano. Con la finalidad de determinar la relación de las variables riesgos percibido de seguridad, privacidad y desempeño con las variables confianza y actitud. Esto tiene importancia, ya que, la banca por internet se encuentra en constante crecimiento mundial debido a la pandemia surgida por el Covid-19, otorgándole una mayor importancia por parte del consumidor frecuente de la banca. Por ende, se busca determinar la influencia de los riesgos percibidos y si afecta en el uso de la banca por internet. La población sujeta a estudio fueron los clientes de los bancos mayores a 25 años, residentes de Lima Metropolitana. Para la recolección de datos se utilizó como instrumento la encuesta virtual, se estructuró las preguntas siguiendo las dimensiones identificadas para el tema de investigación las cuales son: riesgos percibidos; riesgo de seguridad, privacidad y desempeño; actitud; confianza y uso de la banca por internet.
The main objective of this research is to be able to analyze the risks of internet banking and how they affect the use of the user in the Peruvian banking sector. In order to determine the relationship of the variables perceived security, privacy and performance risks with the variables of trust and attitude. This is important, since online banking is in constant global growth due to the pandemic that arose from Covid-19, giving it greater importance by the frequent consumer of banking. Therefore, it seeks to determine the influence of perceived risks and whether it affects the use of internet banking. The population subject to study was the clients of banks over 25 years of age, residents of Lima. For data collection, the survey was used as an instrument, the questions were structured following the dimensions identified for the research topic, which are: perceived risks; security, privacy and performance risk; attitude; trust and use of internet banking.
Trabajo de investigación
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45

Gouveia, Priscila Suscke. "Socioecologia de Sapajus xanthosternos na Reserva Biológica de Una, sul da Bahia." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/47/47132/tde-02102014-110852/.

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A socioecologia investiga o efeito de fatores ecológicos sobre padrões de sistema social. Para muitos animais, o risco de predação tem sido apontado como a principal força seletiva favorecendo a sociabilidade. Entretanto, como determinante na variação dos sistemas sociais de primatas, esse fator tem sido considerado menos importante do que a competição por alimento. Os objetivos deste estudo foram (1) investigar a influência da disponibilidade de alimento e do risco de predação no uso do habitat pelo grupo estudado, para avaliarmos se o risco de predação é um fator relevante para essa população, (2) caracterizar o sistema social e (3) investigar se o risco de predação e/ou a oferta de alimento afetam o sistema social de Sapajus xanthosternos, espécie Criticamente ameaçada devido à caça e destruição do seu habitat, o que a torna relevante para o teste de hipóteses. Esta pesquisa foi realizada na Reserva Biológica de Una, cuja vegetação é classificada como floresta de tabuleiro e, na qual a população estudada ainda sofre pressão de caça. Um grupo foi acompanhado por 16 meses, num total de 2126 horas. O risco de predação foi avaliado em função do comportamento de vigilância, vocalizações de alarme, encontros com predadores e indícios de caça. Por meio do método focal árvore alimentação avaliamos o tamanho e qualidade das fontes agregadas. As interações agonísticas e afiliativas foram registradas pelo método de todas as ocorrências. A área de vida e os percursos diários foram calculados para avaliarmos a competição indireta intra e entre grupos. Os resultados foram comparados com os obtidos para uma população de S. nigritus e uma de S. libidinosus. O uso do habitat pelo grupo foi influenciado tanto pela distribuição e disponibilidade de recursos alimentares quanto pelo risco de predação. Os macacos-prego na Rebio Una formam grupos grandes e coesos, com filopatria de fêmeas e, a população é caracterizada por fissão de grupos grandes. O grande tamanho dos grupos favorece a hipótese de que o tamanho mínimo de grupo é determinado pelo risco de predação. O grupo apresentou um elevado número de machos (esperado devido ao número de fêmeas), o que também é considerado por alguns estudos como evidência de alto risco de predação. A estratégia reprodutiva das fêmeas foi relacionada à organização social e, consequentemente, ao risco de predação. S. xanthosternos consome tanto recursos agregados quanto dispersos e despendeu uma alta proporção de tempo forrageando por invertebrados. A hierarquia de dominância entre fêmeas foi parcial e as fêmeas de alto posto alimentaram-se conjuntamente com as fêmeas de baixo posto em fontes agregadas, enfatizando que fêmeas apresentaram relações tolerantes. A maioria das fontes agregadas utilizadas foi de tamanho intermediário em relação ao tamanho do grupo e produtiva e a competição direta por alimento envolvendo fêmeas intra-grupo não foi baixa. A competição indireta intra-grupo foi elevada, o que se constata pelas altas taxas de deslocamento e pelas grandes distâncias diárias percorridas. A competição direta entre grupos foi baixa e o risco de predação percebido foi alto em comparação com outros estudos. O padrão de sistema social, com grupo grande, elevado número de machos, e fêmeas com alto grau de afiliação e tolerância não está de acordo com o esperado por modelos que só consideram o efeito da competição por alimento, e sugere que o risco de predação afeta os componentes que caracterizam o sistema social deste grupo. Em conclusão, o sistema social de S. xanthosternos nesta população é uma resposta à pressão de predação e à oferta de alimento
Socioecology studies the effect ecological factors have on social system patterns. The predation risk has been said as the main selective force to favoring the sociability in many animals. However, as a determinant in variation of primates social systems, this fact has been considered less important than competition for food. The objectives of this study were (1) investigating how much the availability of food and the predation risk affect the habitat use by the group followed, in order to evaluate if the predation risk is a relevant issue in this population, (2) characterizing the social system and (3) investigating if the predation risk and/or availability of food affect the social system of Sapajus xanthosternos, a critically endangered species, owing to its hunting and habitat destruction, such fact makes it relevant for the hypothesis test. This study was made at the Una Biological Reserve, where the vegetation is classified as tabuleiro forest. The population in focus suffers from hunting stress. A group was followed during 16 months, a total of 2126 hours. The predation risk was evaluated concerning their vigilance behaviour, alarm vocalization, encounters with predators and hunting indication. We evaluated the size and the quality of the clumped food sources through the focal tree food method. Agonistic and affiliative interactions were recorded through all occurrences method. Home range and the daily traveling distances were calculated to evaluate if females experienced scramble competition within and between groups. The results were compared to the ones that had been obtained from a previous study with the population of the species S. nigritus and S. libidinosus. The use of habitat by the group was not only influenced by the distribution and availability food resources but also by the predation risk. The capuchin monkeys in Rebio Una live in large and cohesive groups, show female philopatry, and fission of very large groups. The large size of the groups favours the hypothesis that the minimum size of a group is determined by the predation risk. The group has shown a high number of males (expected due to the high number of females), a fact that is also considered by some studies as evidence of high predation risk. Female reproductive strategies were related to social organization and, therefore, to predation risk. S. xanthosternos consumes clumped and dispersed resources and spent more time foraging for invertebrates. There was a partial dominance hierarchy among females and the high-ranking females ate with the low-ranking females in clumped food sources. Such fact emphasizes that females hold tolerant relations. The majority of used clumped food sources had an intermediate size, concerning the size of the group, and was productive. The contest competition within group for food involving females was not low. Scramble competition within group was high, as shown by the high moving rates and the long daily travel distance. Contest competition between groups was low and the perceived predation risk was high in comparison to other studies. The social system pattern - large group size, high sex ratio, and females that show a high level of affiliation and tolerance - is not in accordance with the expected by models that only consider the result of competition for food. It suggests that the risk of predation affects the elements of social system in this group. As a conclusion, the social system of S. xanthosternos is affected by the risk of predation and food availability
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46

Normandin, Gabrielle. "Lien entre l’accessibilité perçue d’une substance psychoactive et sa consommation : rôle modérateur de la perception du risque à consommer à l’adolescence." Thèse, 2018. http://hdl.handle.net/1866/22222.

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47

"Cannabis Use, Psychotic-like Experiences, and Vascular Risk in Young Adults." Master's thesis, 2016. http://hdl.handle.net/2286/R.I.40726.

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abstract: There is a robust association between psychosis and cannabis use, but the mechanisms underlying this relation are poorly understood. Because both psychosis and cannabis use have been linked to cardiovascular problems, it is possible that cannabis use exacerbates an underlying vascular vulnerability in individuals prone to psychosis. To investigate microvascular differences in individuals with psychotic symptoms and cannabis use, the current study tested associations between psychotic-like experiences, cannabis use, and retinal vessel diameter in 101 young adults (mean age=19.37 years [SD=1.93]). Retinal venular diameter did not differ between participants with (M=218.08, SD=15.09) and without psychotic-like experiences (M=216.61, SD=16.18) (F(1, 97)=0.01, p=.93) or between cannabis users (M=218.41, SD=14.31) and non-users (M=216.95, SD=16.26) (F(1, 97)=0.37, p=.54). Likewise, mean retinal arteriolar diameter did not differ between participants with (M=157.07, SD=10.96) and without psychotic-like experiences (M=154.88, SD=9.03) (F(1, 97)=0.00, p=.97). However, cannabis users had statistically significantly wider retinal arterioles (M=159.10, SD=9.94) than did non-users (M=154.29, SD=10.20) (F(1, 97)=5.99, p=.016), and this effect was robust to control for covariates. There was no evidence of an interaction between psychotic-like experiences and cannabis use in predicting retinal vessel diameter. These results indicate that cannabis use is associated with microvascular differences in young adulthood. Given current trends toward legalization of recreational cannabis use, future research should explore these differences and their potential consequences for cardiovascular health.
Dissertation/Thesis
Masters Thesis Psychology 2016
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48

Van, Niekerk Antoinette Elisabeth. "Cannabis use : social risk factors and knowledge of health risks in a sample of adolescents." Thesis, 1997. http://hdl.handle.net/10413/7944.

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A study was conducted at a Durban high school which has a mixture of socioeconomic classes and races. All grade 10 pupils present on the day of the study were asked to complete a questionnaire under examination-like conditions. The aim was to determine the prevalence of dagga smoking as well as the pupils' knowledge of the effects and health risks of dagga smoking and the prevalence of associated features such as alcohol use, cigarette smoking and sexual activity. Dagga smoking was found to occur commonly (22.9%) and to be mainly a white male group activity. There was a strong association with cigarette smoking and alcohol abuse and a general lack of knowledge concerning the adverse health effects of dagga smoking. Peer pressure and relief of stress were cited as the commonest reasons for dagga smoking. More information and life skills training is required for this group of students as well as further research into substance abuse related topics in general.
Thesis (M.Med.)-University of Natal, Durban, 1997.
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WU, WAN-YING, and 吳琬盈. "A Study of Relationship among Perceived Ease of Use, Perceived Usefulness, Perceived Benefit, Perceived Risk and Collaborative Consumption Attitude." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/fmhx7u.

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碩士
世新大學
公共關係暨廣告學研究所(含碩專班)
105
In recent years, the progressing of Information and Communication Technologies makes people’s consumption pattern changed, and makes the rise of the sharing economy. Nowadays, consumers didn’t just purchase the products to satisfy themselves, but focus on more convenient, eco-friendly and economical way to achieve reciprocity and mutual benefit consumption patterns. However, although the sharing economy has brought many positive benefits, it also hides many risks and crises. Therefore, this study hopes to join the perspective of benefit and risk, through a more comprehensive way to explore influence on perceived ease of use, perceived usefulness, perceived benefits, perceived risk and collaborative consumption attitude. This study used purposive sampling methods, and aimed at users of the "Airbnb Shared Platform". A total of 768 valid questionnaires were recovered. Data are analyzed by frequency analysis、reliability analysis、correlation analysis、SEM、and pooled t-test. The findings are listed as follows: (1) perceived ease of use has a significant impact on perceived usefulness, perceived benefit, perceived risk and collaborative consumption attitude. (2) perceived usefulness has a significant effect on perceived benefit and collaborative consumption attitude. (3) perceived benefit has a significant effect on collaborative consumption attitude. (4) perceived risk has a significant effect on collaborative consumption attitude. Nevertheless, perceived ease of use have no significant influence on collaborative consumption attitude. Thus, the hypothesis is not supported. Although perceived ease of use can not directly affect the collaborative consumption attitude, “perceived ease of use” has the indirect effect on “collaborative consumption attitude” through “perceived benefits”. Consequently, the key what consumers support the sharing platform is the perceived benefit of collaborative consumption.
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HUANG, Tai-Yu, and 黃泰餘. "Research on the application relationship between consumer trust, Perceived Usefulness, Perceived Ease of Use, Perceived risk and Purchase." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/70241005880304375550.

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碩士
國立勤益科技大學
企業管理系
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Mobile applications are crucial to the operations of modern mobile devices. In-Stat estimated that in 2015, the number of app downloads will reach 48 billion, and the global output value of the app industry could be as high as 29 billion USD. Convenience sampling was used for the distribution of questionnaires.The total of 357 questionnaires, and 330 valid questionnaires. We used SPSS to analyze the descriptive statistics and conduct reliability analysis. We also used PLS to conduct empirical analysis on linear SEM. The main findings of this study include the following: (1) Perceived usefulness and perceived ease of use have a positive and significant impact on the purchase intention of consumers, but Perceived risk has a negative and significant impact on the purchase intention of consumers. (2) Trust has a significant impact on the perceived ease of use and perceived usefulness.;Trust has a positive impact on purchase intention through perceived usefulness. (3) Perceived ease of use has a positive and significant impact on the perceived usefulness.;Perceived ease of use has a positive impact on purchase intention through perceived usefulness. (4) Trust has a moderating effect on the relationship of perceived risk and purchase intention.
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