Transparent, Open, and Reproducible Prevention Science.

The field of prevention science aims to understand societal problems, identify effective interventions, and translate scientific evidence into policy and practice. There is growing interest among prevention scientists in the potential for transparency, openness, and reproducibility to facilitate this mission by providing opportunities to align scientific practice with scientific ideals, accelerate scientific discovery, and broaden access to scientific knowledge. The overarching goal of this manuscript is to serve as a primer introducing and providing an overview of open science for prevention researchers. In this paper, we discuss factors motivating interest in transparency and reproducibility, research practices associated with open science, and stakeholders engaged in and impacted by open science reform efforts. In addition, we discuss how and why different types of prevention research could incorporate open science practices, as well as ways that prevention science tools and methods could be leveraged to advance the wider open science movement. To promote further discussion, we conclude with potential reservations and challenges for the field of prevention science to address as it transitions to greater transparency, openness, and reproducibility. Throughout, we identify activities that aim to strengthen the reliability and efficiency of prevention science, facilitate access to its products and outputs, and promote collaborative and inclusive participation in research activities. By embracing principles of transparency, openness, and reproducibility, prevention science can better achieve its mission to advance evidence-based solutions to promote individual and collective well-being.

The Protective Role of Grit against Alcohol and Cannabis Use through Young Adulthood.

Introduction: Problematic substance use in young adulthood is consistently related to negative outcomes later in life. Understanding the factors that protect against problematic substance provides opportunities for early preventive intervention. We examine the protective role of grit - passion and perseverance for long-term goals - on substance use through young adulthood, a period of heightening risks for substance use. Methods: In this research, we use cross-lagged panel models and data from the Victoria Healthy Youth Survey (N = 477, 52% female) to test the reciprocal within-time associations and the directional relationships between grit (passion and perseverance) and substance use (cannabis and alcohol) across three assessments (6 years, ages 18-29). All models controlled for sex and SES. Results: Significant findings show negative within-time associations between passions and perseverance and cannabis use at T1 (ages 18-24) and at T2 (ages 20-26), and significant, negative within-time associations between passion and perseverance and alcohol use (heavy episodic drinking) at T1 but not at T2. No significant across-time associations between passion and perseverance and substance use were found. Conclusion: Preventive interventions to enhance passion and perseverance may provide important targets for interventions for young adults to reduce current substance use. However, grit did not have an effect beyond the stability of cannabis use or alcohol use over time, suggesting effects may act by substituting proactive goals for current substance use.

Disruption of Transitions in High-Risk Substance Use from Adolescence to Young Adulthood: School, Employment, and Romantic Relationship Factors.

Background: Few studies have examined social-contextual moderators of substance use transitions from adolescence to young adulthood. A better understanding of the extent to which school, employment, and romantic relationships can disrupt high-risk use patterns could inform strategies for substance use prevention and treatment.Objective: The current study examines the extent school, employment, and relationship factors can disrupt transition in high-risk substance use patterns from adolescence to young adulthood.Method: Data were collected biennially from 662 youth in six assessments across ten years (2003-2013). Using latent transition analysis (LTA) that examined transition is substance use classes, we examined school, employment, and relationship moderators of use transitions.Results: Few differences were found during adolescence with the most significant findings occurring in the transition from adolescence to young adulthood. Examining the transitions from adolescence to young adulthood (W4 to W6), we found evidence that school, employment, and relationship status disrupted problematic substance use patterns, such that, individuals that indicated entering school, working full-time, or getting married or entering a relationship were more likely to transition to a low-risk substance use class than remain in the high-risk class.Conclusions/Importance: Findings underscore the importance of school completion, obtaining stable career employment, and quality relationship to help reduce high-risk substance use patterns leading into young adulthood. Prevention and intervention efforts should consider the diverse needs of youth and be prepared to provide a wide range of services that include educational opportunities and career development if they want to reduce high-risk substance use patterns.

Patterns of marijuana use and physical health indicators among Canadian youth.

We examine how trajectories of marijuana use in Canadian youth (ages 15 to 28) are related to physical health indicators in adolescence and young adulthood. Youth were initially recruited in 2003 (N = 662; 48% male; ages 12 to 18) and followed for six waves. Five trajectories of marijuana use (Abstainers-29%, Occasional users-27%, Decreasers-14%, Increasers-20% and Chronic users-11%) were identified. Chronic users reported more physical symptoms, poorer physical self-concept, less physical activity, poorer eating practices, less sleep, and higher number of sexual partners during adolescence than other classes. Decreasers also reported poorer physical self-concept and poorer eating practices than abstainers. Other trajectory classes showed few significant health problems. Chronic users also reported more acute health problems (i.e. serious injuries, early sexual debut, higher number of sexual partners, greater likelihood of having a STI) in young adulthood than all other classes contributing to costs of healthcare. Youth who engage in early, frequent and continued use of marijuana from adolescence to young adulthood are at-risk of physical health problems in adolescence and young adulthood.

Is there a positive side to sensation seeking? Trajectories of sensation seeking and impulsivity may have unique outcomes in young adulthood.

INTRODUCTION: High levels of sensation seeking and impulsivity in adolescence are typically associated with risky behaviours; limited research has examined the relation of these traits to positive outcomes. Given that adolescence is a sensitive developmental period that can impact success later in life, we adopt the Positive Youth Development Framework to better understand how the development of self-reported sensation seeking and impulsivity may be differentially related to positive markers of early adulthood. METHOD: Data are from the Victoria Healthy Youth Survey (T1 N = 662; 52% female), a six-wave longitudinal cohort study of Canadian youth. Parallel process latent class growth analysis estimated trajectories of sensation seeking and impulsivity identifying classes of youth (ages 14-28). Controlling for baseline age, sex, and socio-economic status, linear regression analyses examined how longitudinal patterns (classes) of sensation seeking and impulsivity were related to positive markers of early adulthood. RESULTS: Three classes of youth were identified. These varied in levels and trajectories of change in sensation seeking (Ss) and impulsivity (I): LowSs-LowI, 26%; HighSs-HighI, 35%; ModerateSs-LowI, 38%. In young adulthood (T6; ages 22-29), youth in the LowSs-LowI and ModerateSs-LowI classes had significantly higher educational and occupational achievement, and lower financial strain, compared to youth in the HighSs-HighI class. Further, the ModerateSs-LowI class was associated with the highest levels of income and well-being. CONCLUSIONS: Findings identified differential trajectories of sensation seeking and impulsivity, with youth in the ModerateSs-LowI class, followed by the LowSs-LowI class, reporting the most positive outcomes in young adulthood.

Ethical Challenges in Promoting the Implementation of Preventive Interventions: Report of the SPR Task Force.

Prevention science researchers and practitioners are increasingly engaged in a wide range of activities and roles to promote evidence-based prevention practices in the community. Ethical concerns invariably arise in these activities and roles that may not be explicitly addressed by university or professional guidelines for ethical conduct. In 2015, the Society for Prevention Research (SPR) Board of Directors commissioned Irwin Sandler and Tom Dishion to organize a series of roundtables and establish a task force to identify salient ethical issues encountered by prevention scientists and community-based practitioners as they collaborate to implement evidence-based prevention practices. This article documents the process and findings of the SPR Ethics Task Force and aims to inform continued efforts to articulate ethical practice. Specifically, the SPR membership and task force identified prevention activities that commonly stemmed from implementation and scale-up efforts. This article presents examples that illustrate typical ethical dilemmas. We present principles and concepts that can be used to frame the discussion of ethical concerns that may be encountered in implementation and scale-up efforts. We summarize value statements that stemmed from our discussion. We also conclude that the field of prevention science in general would benefit from standards and guidelines to promote ethical behavior and social justice in the process of implementing evidence-based prevention practices in community settings. It is our hope that this article serves as an educational resource for students, investigators, and Human Subjects Review Board members regarding some of the complexity of issues of fairness, equality, diversity, and personal rights for implementation of preventive interventions.

The Effects of Continuities in Parent and Peer Aggression on Relational Intimate Partner Violence in the Transition to Young Adulthood.

Past research suggests that exposure to parent psychological control and peer relational aggression and victimization experienced during adolescence is associated with relational intimate partner violence (IPV) in young adults (ages 22 to 29). However, the effects of continuities in these concerns across young adulthood have not been assessed. Relational IPV is characterized by behaviors intended to damage partner's emotional well-being and security in a romantic relationship (e.g., threatening to break up, purposefully ignoring, or causing jealousy). Six waves of data were collected biennially across 10 years from 662 participants (342 females) who were 12 to 18 years old in 2003. The 334 youth who were in a current romantic relationship at the sixth wave (T6, 10 years later) are the focus of this research. Tests of hypothesized structural equation models indicated that adolescent experiences of psychological control with fathers (but not mothers) predicted relational IPV at T6, but this association was no longer significant after accounting for continuity in father psychological control in young adulthood. Adolescent experiences of relational aggression and victimization with peers also predicted relational IPV at T6. This association remained significant for males, only, after continuity in experiences of relational aggression and victimization with peers in young adulthood was included in the model. Implications for the prevention of relational IPV in adolescence and young adults are discussed.

Frequent marijuana use and driving risk behaviours in Canadian youth.

BACKGROUND: A better understanding of the relations between patterns of marijuana use and driving risks in young adulthood is needed. METHODS: Secondary analyses of self-report data from the Victoria Healthy Youth Survey. Youth (baseline ages 12 to 18; N=662; 52% females) were interviewed biannually (on six occasions) from 2003 to 2013 and classified as abstainers (i.e., used no marijuana in past 12 months), occasional users (i.e., used at most once per week), and frequent users (i.e., used more than once a week). RESULTS: In the frequent user group, 80% of males and 75% of females reported 'being in a car driven by driver (including themselves) using marijuana or other drugs in the last 30 days', 64% of males and 33% of females reported that they were 'intoxicated' with marijuana while operating a vehicle and 50% of males and 42% of females reported being in a car driven by a driver using alcohol. In addition, 28% of occasional users and also a small proportion of abstainers reported 'being in a car driven by a driver using marijuana or other drugs in the last 30 days'. INTERPRETATION: The high frequency of driving risk behaviours, particularly for frequent users, suggest that plans for legalization of recreational use should anticipate the costs of preventive education efforts that present an accurate picture of potential risks for driving. Youth also need to understand risks for dependence, and screening for and treatment of marijuana use disorders is needed.

HISTORIQUE: Il est nécessaire de mieux comprendre les liens entre les habitudes de consommation de marijuana et la conduite à risque chez les jeunes adultes. MÉTHODOLOGIE: Les auteurs ont procédé à des analyses secondaires de données autodéclarées tirées du sondage sur la santé des jeunes de Victoria. Dans ce sondage, les jeunes (de 12 à 18 ans en début d'étude, n=662; 52 % de filles) ont participé à une entrevue tous les deux ans (à six reprises) entre 2003 et 2013. Ils ont été classés comme abstinents (aucune consommation de marijuana dans les 12 mois précédents), consommateurs occasionnels (consommation maximale d'une fois par semaine) et consommateurs fréquents (consommation plus d'une fois par semaine). RÉSULTATS: Dans le groupe des consommateurs fréquents, 80 % des garçons et 75 % des filles ont déclaré « avoir été dans une voiture conduite par une personne (y compris eux-mêmes) qui avait consommé de la marijuana ou d'autres drogues dans les 30 jours précédents ¼, 64 % des garçons et 33 % des filles ont affirmé avoir déjà été « intoxiqués ¼ par la marijuana lorsqu'ils conduisaient une voiture et 50 % des garçons et 42 % des filles ont indiqué avoir été dans une voiture conduite par quelqu'un qui consommait de l'alcool. De plus, 28 % des consommateurs occasionnels et une petite proportion d'abstinents ont déclaré « avoir été dans une voiture conduite par une personne qui avait consommé de la marijuana ou d'autres drogues dans les 30 jours précédents. ¼. INTERPRÉTATION: Compte tenu de la forte fréquence de conduite à risque, notamment chez les consommateurs fréquents, le projet de légaliser la consommation récréative devrait tenir compte des coûts de mesures d'éducation préventive qui présenteront un portrait précis des risques potentiels liés à la conduite. Les jeunes doivent également comprendre les risques de dépendance. Enfin, il est important de procéder au dépistage et au traitement des troubles liés à la consommation de marijuana.

Enhancing Social Responsibility and Prosocial Leadership to Prevent Aggression, Peer Victimization, and Emotional Problems in Elementary School Children.

Testing the theories that form the basis of prevention programs can enhance our understanding of behavioral change and inform the development, coordination, and adaptation of prevention programs. However, theories of change showing the linkages from intervention program components to risk or protective factors to desired outcomes across time are rarely specified or tested. In this 2-year longitudinal study, we test the theory that increases in two protective factors (i.e., children's prosocial leadership and their teachers' expectations of social responsibility) targeted by the WITS Programs (Walk Away, Ignore, Talk it Out, and Seek Help) would be associated with declines in peer victimization, aggression, and emotional problems. Participants included Canadian students, in grades 1-4 at baseline (n = 1329) and their parents and teachers. Consistent with our theory of change, variability in program implementation (adherence and integration) and in children's use of program skills (child responsiveness) are related to increases in both protective factors. Increases in these protective factors are associated with subsequent declines in children's aggression, victimization, and emotional problems. We discuss how enhancement of these protective factors may operate to improve child outcomes and the need for theory-based research to refine and improve the effectiveness of intervention strategies and to improve program scale-up.

Planning for Sustainability of an Evidence-Based Mental Health Promotion Program in Canadian Elementary Schools.

Substantial research illuminates many factors effecting the implementation of evidence-based mental health promotion programs in schools; however, research on how schools plan for sustaining their investments in these programs is limited. In this qualitative study, we elicited descriptions of opportunities and challenges for sustainability. We interviewed 24 individuals from schools involved in a longitudinal, qualitative research project that followed uptake and implementation of the evidence-based WITS Programs across 2 years (Leadbeater et al. 2012). WITS stands for Walk away, Ignore, Talk it out and Seek help and the online WITS Programs focus on preventing peer victimization ( www.witsprograms.ca ). Our findings suggest that sustainability planning in schools is not merely a next step following high quality implementation, but rather involves multiple ongoing processes that need to be anticipated and supported by school leadership and program champions and developers in order to realize investments in evidence-based programs.

It gets better or does it? Peer victimization and internalizing problems in the transition to young adulthood.

Consistent research shows that peer victimization predicts internalizing symptoms in childhood and adolescence, but the extent to which peer victimization and its harmful effects on mental health persists into young adulthood is unclear. The current study describes patterns of physical and relational victimization during and after high school, and examines concurrent and prospective associations between internalizing symptoms (depressive and anxious symptoms) and peer victimization (physical and relational) from adolescence to young adulthood (ages 12-27). Data were collected from the Victoria Healthy Youth Survey, a five-wave multicohort study conducted biennially between 2003 and 2011 (N = 662). Physical victimization was consistently low and stable over time. Relational victimization increased for males after high school. Both types of victimization were associated concurrently with internalizing symptoms across young adulthood for males and for females. Although sex differences were important, victimization in high school also predicted increases in internalizing problems over time.

Results of a randomized controlled trial of the cannabis eCHECKUP TO GO personalized normative feedback intervention on reducing cannabis use, cannabis consequences, and descriptive norms.

BACKGROUND: The prevalence of cannabis use disorder and its negative consequences among young adults has highlighted the need for prevention and early intervention programs. However, low treatment prevalence persists due to factors such as lack of perceived need, concerns about stigma, and limited access to treatment. To address these barriers, web-based cannabis interventions have been developed, but their efficacy remain limited. This study aims to evaluate the cross-site efficacy of the Cannabis eCHECKUP TO GO program, a web-based Personalized Normative Feedback and Protective Behavioral Strategies intervention for reducing cannabis use frequency and consequences in college students with willingness to change. METHODS: Participants were 781 students from three universities (two in Canada, one in the US) who reported using cannabis in the past month and expressed interest in reducing or engaging in safer cannabis use. The study randomly assigned them to either an experimental group that received personalized normative feedback or a control group that received information on healthy stress management. The study collected follow-up data 4 weeks after the initial intervention and measured participants' frequency of cannabis use, number of cannabis consequences, descriptive and injunctive norms at both time points. RESULTS: The results showed no significant reductions in cannabis use or negative consequences of use. However, students who received personalized normative feedback experienced a significant reduction in descriptive norms related to cannabis use, to be more in line with actual use. CONCLUSION: This study suggests that more targeted interventions may be necessary for university students who are already using and seeking help to reduce their use.

Trajectories of oppositional defiant disorder severity from adolescence to young adulthood and substance use, mental health, and behavioral problems.

Background: Oppositional Defiant Disorder (ODD) is a disruptive behavioral disorder; however, increasing evidence emphasizes irritable mood as a primary symptom of ODD. Objectives: This study investigated whether heterogeneous groups (classes) of individuals can be differentiated based on ODD sub-dimensions (irritability and defiance) or on overall ODD symptoms longitudinally. We also examine associations between ODD trajectory class and comorbid substance use (heavy episodic drinking, cannabis use), mental health (depression and anxiety) and behavioral symptoms (ADHD, aggression and substance use) in both adolescence and young adulthood (controlling for adolescent levels of each of these concerns). Method: Data were from a randomly recruited community sample of 662 Canadian youth (T1 ages 12-18) followed biennially for 10 years (T6 ages 22-29). Results: Growth mixture models revealed trajectories classes of ODD based on severity of symptoms. A three-class solution provided the best fit with Low (n = 119; 18%), Moderate (n = 473; 71.5%), and High (n = 70; 10.6%) ODD classes. Class trajectory differences were similarity based on symptoms severity (rather than type) for symptom sub-dimensions (irritability defiance). Adolescent and young adult substance use, mental health symptoms, and behavioral problems were significantly higher for the High ODD trajectory class compared to both other classes. Youth in the Moderate ODD trajectory class also showed higher comorbid symptoms in adolescence and young adulthood, compared to the Low ODD trajectory class. Conclusion: Early identification of children and adolescents with high or moderate ODD symptoms and interventions that simultaneously address defiance and irritability are supported by the findings.

Contexte: Le trouble oppositionnel avec provocation (TOP) est un trouble du comportement perturbateur; toutefois, des données probantes croissantes soulignent que l'humeur irritable est un symptôme primaire du TOP. Objectifs: La présente étude a investigué si les groupes (classes) hétérogènes de personnes qui peuvent être différentiées au mieux selon les sous-dimensions (irritabilité et défi) ou selon les symptômes généraux du TOP longitudinalement. Nous examinons également les associations entre la classe de trajectoire du TOP et l'utilisation de substances comorbide (lourde consommation d'alcool épisodique, utilisation de cannabis), la santé mentale (dépression et anxiété) et symptômes comportementaux (TDAH, agression et utilisation de substances) tant chez les adolescents que chez les jeunes adultes (contrôler les niveaux adolescents de chacun de ces problèmes). Méthode: Les données provenaient d'un échantillon communautaire recruté au hasard de 662 jeunes Canadiens (âges T1 2­18) suivis tous les deux ans pendant 10 ans (T6 âges 22­29). Résultats: Des modèles de mélange de croissance ont révélé des classes de trajectoire du TOP basées sur la gravité des symptômes. Une solution en trois classes a fourni le meilleur ajustement avec des classes de TOP faible (n = 119; 18 %), modérée (n = 473; 71,5 %), et élevée (n = 70; 10,6 %). Les différences de classes de trajectoire étaient également basées sur la gravité des symptômes (plutôt que sur le type) des sous-dimensions des symptômes (irritabilité, défi). L'utilisation de substances chez les adolescents et les jeunes adultes, les symptômes de santé mentale et les problèmes de comportement étaient significativement plus élevés pour la classe de la trajectoire élevée du TOP comparé aux deux autres classes. Les jeunes de la classe de trajectoire modérée du TOP présentaient aussi des symptômes comorbides plus élevés à l'adolescence et au jeune âge adulte, comparé à la classe de trajectoire faible du TOP. Conclusion: L'identification précoce des enfants et des adolescents présentant des symptômes élevés ou modérés du TOP et les interventions qui prennent en charge simultanément le défi et l'irritabilité sont soutenues par les résultats.

Child and context characteristics in trajectories of physical and relational victimization among early elementary school children.

Transactional models suggest that peer victimization results from both individual and context differences, and understanding these differences may point to important targets for prevention and interventions that reduce victimization. Multilevel modeling was used to examine within-person (aggression and emotional dysregulation), between-person (sex and age), and between-school (participation in a victimization prevention program) factors that influence changes in physical and relational victimization over the first three years of elementary school. Children (n = 423) reported their experiences of peer victimization at entry into Grade 1 and at the end of Grade 1, Grade 2, and Grade 3. On average, trajectories of both physical and relational victimization declined. However, for individual children, teacher-rated aggression was associated with increases in physical and relational victimization, while emotional dysregulation was associated with attenuation of longitudinal declines in physical victimization and increases in relational victimization. Individual differences in sex and age at entry into Grade 1 did not significantly influence victimization trajectories over Grades 1 to 3. Children who participated in the WITS® victimization prevention program showed significant declines in physical and relational victimization. Levels of victimization among nonparticipants remained stable. Implications of child and context characteristics for preventing peer victimization in elementary school are discussed.

Relational victimization and depressive symptoms in adolescence: moderating effects of mother, father, and peer emotional support.

Adolescence heralds a unique period of vulnerability to depressive symptoms. This longitudinal study examined relational victimization in adolescents' peer relationships as a unique predictor of depressive symptoms among a primarily (85%) Caucasian sample of 540 youth (294 females) concurrently and across a 6-year period. The moderating effects of emotional support received from mothers, fathers, and peers on the association between relational victimization and adolescents' depressive symptoms were also investigated. Findings revealed that adolescents who were relationally victimized consistently had higher depressive symptoms than their non-victimized peers. However, high levels of emotional support from fathers buffered this relationship over time. Emotional support from mothers and peers also moderated the longitudinal relationship between relational victimization and depressive symptoms, with high levels of support predicting increases in adolescents' symptoms. Relational victimization presents a clear risk for depressive symptoms in adolescence, and emotional support may serve either a protective or vulnerability-enhancing role depending on the source of support.

The effects of peer victimization and physical aggression on changes in internalizing from first to third grade.

Three models of the prospective relations between child maladjustment and peer victimization are examined: (a) internalizing results directly from victimization, (b) internalizing leads to victimization, and (c) physical aggression fuels retaliatory victimization that leads to increases in internalizing over time. Data came from assessments of children at the beginning of Grade 1 (n = 432; average age = 6.3 years), with follow-ups at the end of Grades 1, 2, and 3. Most children showed low stable internalizing trajectories (73%); however, high stable and increasing curvilinear trajectories were evident for 7% and 20% of children, respectively. Findings suggest that children's adjustment problems at entry to Grade 1 affect the course of their internalizing, in part, by setting the stage for peer victimization.

Age-varying effects of cannabis use frequency and disorder on symptoms of psychosis, depression and anxiety in adolescents and adults.

AIMS: We tested the age-varying associations of cannabis use (CU) frequency and disorder (CUD) with psychotic, depressive and anxiety symptoms in adolescent and adult samples. Moderating effects of early onset (≤ 15 years) and sex were tested. DESIGN: Time-varying effect models were used to assess the significance of concurrent associations between CU and CUD and symptoms of psychosis, depression and anxiety at each age. SETTING AND PARTICIPANTS: Adolescent data (V-HYS; n = 662) were collected from a randomly recruited sample of adolescents in Victoria, British Columbia, Canada during a 10-year period (2003-13). Adult cross-sectional data (NESARC-III; n = 36 309) were collected from a representative sample from the United States (2012-13). MEASUREMENTS: Mental health symptoms were assessed using self-report measures of diagnostic symptoms. CU was based on frequency of past-year use. Past-year CUD was based on DSM-5 criteria. FINDINGS: For youth in the V-HYS, CU was associated with psychotic symptoms following age 22 [b = 0.13, 95% confidence interval (CI) = 0.002, 0.25], with depressive symptoms from ages 16-19 and following age 25 (b = 0.17, 95% CI = 0.003, 0.34), but not with anxiety symptoms. CUD was associated with psychotic symptoms following age 23 (b = 0.51, 95% CI = 0.01, 1.01), depressive symptoms at ages 19-20 and following age 25 (b = 0.71, 95% CI = 0.001, 1.42) and anxiety symptoms ages 26-27 only. For adults in the NESARC-III, CU was associated with mental health symptoms at most ages [e.g. psychotic symptoms; age 18 (b = 0.22, 95% CI = 0.10, 0.33) to age 65 (b = 0.36, 95% CI = 0.16, 0.56)]. CUD was associated with all mental health symptoms across most ages [e.g. depressive symptoms; age 18 (b = 0.96, 95% CI = 0.19, 1.73) to age 61 (b = 1.11, 95% CI = 0.01, 2.21)]. Interactions with sex show stronger associations for females than males in young adulthood [e.g. V-HYS: CUD × sex interaction on psychotic symptoms significant after age 26 (b = 1.12, 95% CI = 0.02, 2.21)]. Findings were not moderated by early-onset CU. CONCLUSIONS: Significant associations between cannabis use (CU) frequency and disorder (CUD) and psychotic and depressive symptoms in late adolescence and young adulthood extend across adulthood, and include anxiety.

How much can you drink before driving? The influence of riding with impaired adults and peers on the driving behaviors of urban and rural youth.

AIMS: Following an ecological model to specify risks for impaired driving, we assessed the effects of youth attitudes about substance use and their experiences of riding in cars with adults and peers who drove after drinking alcohol or smoking cannabis on the youths' own driving after drinking or using cannabis. DESIGN AND METHODS: Participants were 2594 students in grades 10 and 12 (mean age = 16 years and 2 months; 50% girls) from public high schools in urban (994) and rural communities (1600) on Vancouver Island in British Columbia, Canada; 1192 of these were new drivers with restricted licenses. Self-report data were collected in anonymous questionnaires. Regression analyses were used to assess the independent and interacting effects of youth attitudes about substance use and their experiences of riding in cars with adults or peers who drove after drinking alcohol or smoking cannabis on youth driving. FINDINGS: Youth driving risk behaviors were associated independently with their own high-risk attitudes and experiences riding with peers who drink alcohol or use cannabis and drive. However, risks were highest for the youth who also report more frequent experiences of riding with adults who drink alcohol or use cannabis and drive. CONCLUSIONS: Prevention efforts should be expanded to include the adults and peers who are role models for new drivers and to increase youths' awareness of their own responsibilities for their personal safety as passengers.

Victimization and Relational Aggression in Adolescent Romantic Relationships: The Influence of Parental and Peer Behaviors, and Individual Adjustment.

Consistent with the view that adolescent relationships are established in the context of important characteristics of their social networks, we examined the effects of adolescents' experiences of parenting (psychological control and positive monitoring) and of peer aggression and victimization, on their self reports of dating victimization and aggression. We also examined the effects of individual differences in emotional and behavioral problems. We used questionnaire data from a population-based sample of youth 12-18 years old who were in dating relationships (n = 149). Parental monitoring emerged as a protective factor in reducing both dating victimization and relational aggression. Our findings also point to a significant transfer of aggression in peer relationships to relational aggression in dating relationships.

Depressive symptom trajectories and physical health: Persistence of problems from adolescence to young adulthood.

BACKGROUND: We examine how depressive symptom trajectories are related to adolescent and young adult subjective health, health-promoting, health-risk, and sexual risk behaviors, as well as cardiometabolic risks. METHOD: Data came from a community-based sample of youth (N = 662; 52% female) followed biannually, six times across 10 years. Latent class growth analysis identified four depressive symptom trajectories which were compared on adolescent (T1; ages 12-18) and young adult (T6; ages 22-29) health indicators. RESULTS: The Low stable trajectory (49%) showed the fewest health risks. The Persistent high trajectory (9%) reported higher physical symptoms, lower physical self-concept, less physical activity and sleep, and higher rates of smoking and sexual risk behaviors than the Low stable trajectory and risks for physical symptoms, physical self-concept, and physical activity worsened in young adulthood. Increasers (21%) showed risks for physical symptoms, physical activity, and sleep in adolescence and problems for physical symptoms and physical self-concept persisted in young adulthood. Decreasers (22%) showed risks for physical symptoms, physical self-concept, physical activity, and sleep in adolescence but these risks resolved into young adulthood. LIMITATIONS: Findings may not generalize to ethnic minorities. Sex differences were not examined due to sample size limitations and most variables, except cardiometabolic risks, were self-reported. CONCLUSIONS: Findings suggest early treatment of depressive symptoms that includes strategies addressing physical symptoms, physical self-concept, and physical activity may prove beneficial. Screening youth for physical symptoms and declines in health-promoting behaviors may also identify youth at risk of depression onset and progression.