The Impact of the Good Behavior Game on Risk for Drug Use Disorder in an Agent-Based Model of Southern Sweden.

OBJECTIVE: Drug use disorder (DUD) is a worldwide problem, and strategies to reduce its incidence are central to decreasing its burden. This investigation seeks to provide a proof of concept for the ability of agent-based modeling to predict the impact of the introduction of an effective school-based intervention, the Good Behavior Game (GBG), on reducing DUD in Scania, Sweden, primarily through increasing school achievement. METHOD: We modified an existing agent-based simulation model of opioid use disorder to represent DUD in Scania County, southern Sweden. The model represents every individual in the population and is calibrated with the linked individual data from multiple sources including demographics, education, medical care, and criminal history. Risks for developing DUD were estimated from the population in Scania. Scenarios estimated the impact of introducing the GBG in schools located in disadvantaged areas. RESULTS: The model accurately reflected the growth of DUD in Scania over a multiyear period and reproduced the levels of affected individuals in various socioeconomic strata over time. The GBG was estimated to improve school achievement and lower DUD registrations over time in males residing in disadvantaged areas by 10%, reflecting a decrease of 540 cases of DUD. Effects were considerably smaller in females. CONCLUSIONS: This work provides support for the impact of improving school achievement on long-term risks of developing DUD. It also demonstrated the value of using simulation modeling calibrated with data from a real population to estimate the impact of an intervention applied at a population level.

Expanded Tunability of Intraparticle Frameworks in Spherical Heterostructured Nanoparticles through Substoichiometric Partial Cation Exchange.

Partial cation exchange reactions provide a synthetic pathway for rationally constructing heterostructured nanoparticles that incorporate different materials at precise locations. Multiple sequential partial cation exchange reactions can produce libraries of exceptionally complex heterostructured nanoparticles, but the first partial exchange reaction is responsible for defining the intraparticle frameworks that persist throughout and help to direct subsequent exchanges. Here, we studied the partial cation exchange behavior of spherical nanoparticles of roxbyite copper sulfide, Cu1.8S, with substoichiometric amounts of Zn2+. We observed the formation of ZnS-Cu1.8S-ZnS sandwich spheres, which are already well known in this system, as well as ZnS-Cu1.8S Janus spheres and Cu1.8S-ZnS-Cu1.8S central band spheres, which have not been observed previously as significant subpopulations of samples. Aliquots taken during the formation of the heterostructured nanoparticles suggest that substoichiometric amounts of Zn2+ limit the number of sites per particle where exchange initiates and/or propagates, thereby helping to define intraparticle frameworks that are different from those observed using excess amounts of exchanging cations. We applied these insights from mixed-population samples to the higher-yield synthesis of ZnS-Cu1.8S Janus spheres, as well as the higher-order derivatives ZnS-(CdS-Cu1.8S), ZnS-(CdS-ZnS), and ZnS-(CdS-CoS), which have unique features relative to previously reported analogues. These results demonstrate how the diversity of intraparticle frameworks in spherical nanoparticles can be expanded to produce a broader range of downstream heterostructured products.

The conditioning effects of positive experiences on the ACEs-offending relationship in adolescence.

BACKGROUND: Research shows that adverse childhood experiences (ACEs) are problematic and may impact delinquency and arrest in adolescence. However, resiliency theories suggest the association between ACEs and delinquency/arrest may be mitigated by positive childhood experiences (PCEs). OBJECTIVE: This study tests the hypothesis that an accumulation of PCEs ameliorates the relationship between ACEs and delinquency and arrest during adolescence. PARTICIPANTS AND SETTING: Prospective data were collected from approximately 800 participants in the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN). METHODS: Self-report data from 16-year-old participants were used to measure the two dependent variables: the number of delinquent acts committed and having at least one arrest in the past year. Count measures reflected the number of ACEs and PCEs, with the former based on reports from child protective services, caregivers, and youth collected from ages 4-12, and the latter based on self-reports at age 12. Negative binomial models analyzed delinquency outcomes, logistic regression models examined arrest, and interaction terms assessed moderating effects. RESULTS: ACEs were associated with significantly more delinquent acts but not arrest, and PCEs were associated with significantly fewer delinquent acts but not arrest. PCEs significantly reduced the relationship between ACEs and delinquency but only for youth with moderate levels of ACEs. CONCLUSIONS: Findings indicate a need for additional research measuring the moderating effects of a variety of PCEs and to the need to enhance positive experiences for youth to prevent delinquency.

Orthogonal reactivity and interface-driven selectivity during cation exchange of heterostructured metal sulfide nanorods.

We report predictive guidelines for the substoichiometric cation exchange of model two-component metal sulfide nanorods containing divalent cations of similar hardness. Unit cell volume changes, cation radii, solubility constants, and solid state interfaces influence selectivity during substoichiometric exchange of Cu+ when multiple products are possible.

Adverse Childhood Experiences and Adolescent Exposure to Violence.

Adverse childhood experiences (ACEs) are relatively common and can lead to harmful outcomes in adolescence and adulthood. The current study investigates the relationship between ACEs and exposure to violence in adolescence, an important area of research given the high rates of victimization in adolescence and the need for evidence-based strategies to prevent and reduce the negative consequences of victimization. The study also examines sex differences in the effects of ACEs, given that some research finds that the prevalence and impact of ACEs vary for females and males. Research questions were analyzed using prospective data from 766 to 773 high-risk youth and caregivers participating in the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN). A total of 10 ACEs were assessed, including five types of child maltreatment measured using official data from child protective services agencies and five types of household dysfunction reported primarily by caregivers. Exposure to three types of violence (verbal intimidation, physical victimization, and witnessing violence) were measured using youth self-reports. Logistic regression analyses examined the relationship between the number of ACEs experienced before age 12 and the likelihood of violence exposure from ages 15 to 18. Youth experiencing more ACEs had a significantly greater likelihood of physical victimization (with an adjusted odds ratio of 1.15), but not intimidation (Adjusted Odds Ratio [AOR] = 1.10) or witnessing violence (AOR = 1.11). Sex did not significantly moderate these relationships, but in sex-specific analyses, ACEs significantly increased intimidation and victimization for girls and witnessing violence for boys. Although the findings showed inconsistent evidence of a relationship between ACEs and exposure to violence, they support the need for interventions to reduce ACEs and their impact on exposure to violence during adolescence.

Evidence for a Causal Relationship Between Academic Achievement and Cigarette Smoking.

INTRODUCTION: Academic achievement (AA) is associated with smoking rates. Can we determine the degree to which this relationship is likely a causal one? METHODS: We predict smoking in male conscripts (mean age 18.2) assessed from 1984 to 1991 (N = 233 248) and pregnant females (mean age 27.7) receiving prenatal care 1972-1990 (N = 494 995) from AA assessed in all students at 16. Instrumental variable (IV) analyses used the instrument month-of-birth as in each school year, older children have high AA. Co-relative analyses used AA-smoking associations in the population, cousins and siblings to predict the AA-smoking relationship in MZ twins, thereby controlling for familial confounding. RESULTS: In males, higher AA was associated with a substantial decrease in risk for smoking (odds ratio [OR] [95% confidence intervals [CIs]] per standard deviation [SD] = 0.41 [0.40-0.41]) while the parallel figures obtain from our IV and co-relative analyses were 0.47 (0.39-0.57) and 0.51 (0.43-0.60), respectively. In females, these figures for pre-pregnancy smoking were, respectively, 0.39 (0.39-0.39), 0.50 (0.46-0.54) and 0.54 (0.51-0.58). Results for heavy versus light smoking suggested a causal effect but were inconsistent across methods. However, among females smoking prior to pregnancy, AA predicted a reduced risk for continued smoking with ORs for uncontrolled, IV, and co-relative analyses equaling, respectively, were 0.54 (0.53-0.55) 0.68 (0.56-0.82) and 0.78 (0.66-0.91), respectively. CONCLUSIONS: Two different methods produced consistent evidence that higher AA has a causal effect on reducing smoking rates and increasing cessation rates in smoking pregnant females. Improving AA may result in meaningful gains in population health through reduced smoking. IMPLICATIONS: This study provides consistent evidence across two different methods that high AA is causally related to reduced rates of smoking and increasing rates of smoking cessation among pregnant women. Our results suggest that interventions that improve educational achievement in adolescence would reduce tobacco consumption, thereby improving public health.

The causal effect of resilience on risk for drug abuse: a Swedish national instrumental variable, co-relative and propensity-score analysis.

BACKGROUND: We sought to quantify and investigate the causal nature of the association between resilience at age 18 and future drug abuse (DA). METHOD: In a national sample of Swedish men (n = 1 392 800), followed for a mean of 30.3 years, resilience was assessed during military conscription and DA defined from medical, criminal and pharmacy registers. For causal inference, we utilized three methods: (i) instrumental variable analyses with the month of birth as the instrument; (ii) co-relative analyses using the general population, cousins, siblings and monozygotic twins; and (iii) propensity scoring on a subsample (n = 48 548) with strong resilience predictors. Cox proportional hazards models were utilized to examine survival time till DA diagnosis. RESULTS: Low resilience was most robustly predicted from internalizing symptoms. Lower levels of standardized resilience strongly predicted the risk for DA (HR = 2.31, 95% CIs 2.28-2.33). In instrumental, co-relative, and propensity score analyses, the association between resilience and DA was estimated at HR = 3.06 (2.44-3.85), 1.34 (1.28-1.39), and 1.40 (1.28-1.53), respectively. Sensitivity analyses suggested that our instrument was weak and, despite our large sample, likely under-estimated confounding. CONCLUSIONS: Low resilience strongly predicts DA risk. Three different causal analysis methods, with divergent assumptions, concurred in estimating that an appreciable proportion of this association was causal, probably around 40%, with the remainder arising from confounding variables many of which are likely familial. Consistent with prior interventions focused on substance use prevention, our results suggest that prevention programs that increase resilience in adolescence should meaningfully reduce the long-term risk for DA.

Synthetic Control of Hot-Electron Thermalization Efficiency in Size-Tunable Au-Pt Hybrid Nanoparticles.

Gold nanoparticles are well-known to exhibit size-dependent properties that are responsible for their unique catalytic, optical, and electronic applications. However, electron-phonon coupling, which is important for photocatalysis and light harvesting, is one of the rare properties of gold that is size-independent above a threshold value, e.g., for nanospheres larger than approximately 5 nm in diameter. Here, we show that when interfaced to a comparably sized Pt nanoparticle, the electron-phonon coupling constant of the hybrid material depends on the diameter of the Au domain. This is important because the electron-phonon coupling constant describes the efficiency by which hot electrons are converted to local heat by the primary electron-phonon scattering thermalization channel. We begin by synthesizing a library of Au-Pt hybrid nanoparticle heterodimers by growing size-tunable Au nanoparticles on Pt nanoparticle seeds. By systematically varying reagent concentration and reaction time, the Au domain diameter of the Au-Pt hybrid nanoparticle heterodimers can be tuned between 4.4 and 16 nm while the size of the Pt domain remains constant. Calibration curves allow us to dial in precise Au domain sizes, and microscopic analysis of the Au-Pt heterodimers provides insights into how they grow and how their morphologies evolve. Femtosecond time-resolved transient absorption spectroscopy reveals that for Au-Pt heterodimers having Au domain diameters of 8.7 to 14 nm, the electron-phonon coupling constant decreases by more than 80%, which is not observed for comparably sized Au nanoparticles. Interfacing smaller Au domains with Pt nanoparticle surfaces causes an increase in the density of states near the Fermi level of Au, which results in accelerated thermalization times through an increased number of electron-phonon interactions. The combination of precision hybrid nanoparticle synthesis and size-dependent electron-phonon coupling may be important for designing composite metals for photocatalytic and light-harvesting applications and for engineering different functions into established materials.

The Society for Prevention Research 20 Years Later: a Summary of Training Needs.

The Society for Prevention Research (SPR) aims to continually provide relevant professional development training opportunities to advance scientific investigation of ways to improve the health, well-being, and social and educational outcomes of individuals and communities. Our study, led by the Training Needs Assessment Task Force, designed a quantitative questionnaire informed by semistructured, qualitative interviews of 13 key prevention science informants. The questionnaire was deployed to all SPR members, of which 347 completed it. Questions about training topics were asked along 8 categories: (1) theory; (2) preventive interventions; (3) research methods, design, and evaluation; (4) teaching and mentoring; (5) practical and interpersonal skills; (6) communication; (7) project management; and (8) data analysis. Across all categories, respondents reported a high level of interest in receiving training: more than 80% were interested in training in data analytic methods; about 70% indicated interest in theory, preventive interventions, and research methods, design, and evaluation; about 65% were interested in at least 1 communication and project management topic; and 60% showed interest in at least 1 practical and interpersonal skills topic. Training-related interests varied across career level and race/ethnicity, with early-career individuals and people of color typically indicating the most interest. Participants were most likely to endorse self-initiated learning and webinars. SPR preconference training workshops were strongly endorsed for data analysis and preventive intervention topics. Recommendations from our study include a need for SPR to more strongly support self-initiated learning opportunities and continue preconference training programs, with special focuses in statistical methods and preventive interventions and regular assessment of members' training preferences.

Nature of the Causal Relationship Between Academic Achievement and the Risk for Alcohol Use Disorder.

OBJECTIVE: We evaluated the claim that interventions to improve academic achievement can reduce the risk for alcohol use disorder (AUD). METHOD: Using nationwide data for individuals born in Sweden from 1972 to 1981 (n = 930,182), we conducted instrumental variable and co-relative analyses of the association between academic achievement and AUD with a mean 21.4-year follow-up. Our instrument, used in the instrumental variable analyses, was month of birth. Co-relative analyses were conducted in cousins, full siblings, and monozygotic twins discordant for AUD, with observed results fitted to a genetic model. The academic achievement-AUD association was modeled in Cox regression. AUD was assessed using national medical, criminal, or pharmacy registries. RESULTS: Later month of birth was significantly associated with poorer academic achievement. Lower standardized academic achievement had a strong relationship with the risk for subsequent AUD registration: hazard ratio (HR) [per SD] = 2.14 [2.11, 2.17]. Instrumental variable analysis produced a substantial but moderately attenuated association: HR = 1.52 [1.28, 1.80]. Controlling for modest associations between month of birth and parental education and AUD risk reduced the association to HR = 1.43 [1.20, 1.69]. Our genetic co-relative model fitted the observed data relatively well and estimated the academic achievement-AUD association in monozygotic twins discordant for academic achievement to equal an HR of 1.44 [1.35, 1.52]. Results were broadly similar when analyzed separately in males and females. CONCLUSIONS: Two distinct methods with different assumptions produced results suggesting that the association observed between academic achievement at age 16 and the risk for AUD into middle adulthood is partly causal, thereby providing support for interventions to improve academic achievement as a means to prevent later AUD risk.

Making Evidence-Based Interventions Relevant for Users: A Comparison of Requirements for Dissemination Readiness Across Program Registries.

This study compares prevention program registries in current use on their level of support for users seeking to implement evidence-based programs. Despite the importance of registries as intermediaries between researchers and the public, and although previous studies have examined how registries define their standards for methodological soundness and evidence of efficacy, little research has focused on the degree to which registries consider programs' dissemination readiness. The result is that registry users are uncertain whether listed programs and their necessary support materials are even available for implementation. This study evaluates 11 publicly and privately funded prevention registries that review the evidence base of programs seeking to improve child health and prosocial outcomes on the degree to which they use dissemination readiness as an evidentiary criterion for rating programs, and the extent and type of information they provide about dissemination readiness to support real-world implementation. The results show wide variability, with few having standards about dissemination readiness or making evidence-based information about interventions easily accessible to users. Findings indicate the need for registries to (1) do more to assess dissemination readiness before including programs on their website and (2) offer more complete information on dissemination readiness and implementation support to users.

Perceptions of danger, tolerance of delinquency, and economic disadvantage: Examining neighborhood influences on child physical abuse.

BACKGROUND: Social disorganization theory posits that both structural and social features of a particular geographic unit are associated with criminal behavior. Despite many tests of social disorganization theory, few studies have assessed its relevance to child abuse. OBJECTIVE: This study seeks to explain neighborhood variation in child maltreatment. The goal of the current study is to fill this gap by investigating whether or not child physical abuse is related to neighborhood economic disadvantage, perceptions of the dangerousness of the neighborhood, and norms regarding delinquency. PARTICIPANTS AND SETTING: Data were drawn from the Project on Human Development in Chicago Neighborhoods (PHDCN) and included 2364 respondents from 79 neighborhoods. The dependent variable, the variety or number of acts of severe child physical abuse, was reported by caregivers, while neighborhood characteristics were based on information from the U.S. Census Data and adult respondents living in Chicago neighborhoods. METHODS: A multilevel, over-dispersed, Poisson regression models were utilized to predict the variety of acts of severe physical abuse that a child living within a given neighborhood would experience. RESULTS: Neighborhood economic disadvantage was not significantly associated with greater variety of physical abuse. However, neighborhoods perceived as dangerous had greater variety of physical abuse (b = .25, p < .05), while those with a greater tolerance for deviance had somewhat lower variety of physical abuse (b= -.69, p ≤ .10). CONCLUSIONS: These results suggest that some contextual factors may help explain child maltreatment and should be subject to additional research.

Health determinants of adolescent criminalisation.

Several conditions related to health and development in adolescence can increase the risk that a young person will be exposed to the criminal justice system. Such determinants include neurodevelopmental disability, poor mental health, trauma, and experiences of maltreatment. Furthermore, the risk of exposure to the criminal justice system seems to be amplified by social marginalisation and inequality, such that young people are made susceptible to criminal behaviour and criminalisation by a combination of health difficulties and social disadvantages. This Review presents evidence on the health determinants of criminalisation among adolescents, providing a persuasive case for policy and practice reform, including for investment in approaches to prevent criminalisation on the basis of health and developmental difficulties, and to better address related needs once within a criminal justice system.

Child Maltreatment and Aggressive Behaviors in Early Adolescence: Evidence of Moderation by Parent/Child Relationship Quality.

The cycle of violence suggests that maltreatment increases children's aggression, but research shows that many children are resilient to the harms caused by maltreatment. This study examines whether or not parent/child relationship quality accounts for variation in the impact of maltreatment on aggression and hypothesizes that the effect will be weaker for children who have better relationships with their caregivers. Race differences in these effects are also examined. Based on prospective data from a high-risk sample of 620 (207 White and 413 Black) families in the Longitudinal Studies of Child Abuse and Neglect, ordinary least squares regression analyses indicated that youth with at least one official allegation of maltreatment before age 10 had significantly more frequent aggressive behaviors at age 12. The direct effect of maltreatment on aggression did not vary for Black and White youth. However, a significant three-way interaction indicated that parent/child relationship quality buffered the relationship between maltreatment and aggressive behaviors for White but not Black children. Although additional research is required to identify factors that ameliorate the impact of maltreatment for Black youth, the findings support the need for interventions to help children cope with maltreatment and to strengthen parent/child relationships.

Scaling up Evidence-Based Interventions in US Public Systems to Prevent Behavioral Health Problems: Challenges and Opportunities.

A number of programs, policies, and practices have been tested using rigorous scientific methods and shown to prevent behavioral health problems (Catalano et al., Lancet 379:1653-1664, 2012; National Research Council and Institute of Medicine, 2009). Yet these evidence-based interventions (EBIs) are not widely used in public systems, and they have limited reach (Glasgow et al., American Journal of Public Health 102:1274-1281, 2012; National Research Council and Institute of Medicine 2009; Prinz and Sanders, Clinical Psychology Review 27:739-749, 2007). To address this challenge and improve public health and well-being at a population level, the Society for Prevention Research (SPR) formed the Mapping Advances in Prevention Science (MAPS) IV Translation Research Task Force, which considered ways to scale up EBIs in five public systems: behavioral health, child welfare, education, juvenile justice, and public health. After reviewing other efforts to scale up EBIs in public systems, a common set of factors were identified as affecting scale-up in all five systems. The most important factor was the degree to which these systems enacted public policies (i.e., statutes, regulations, and guidance) requiring or recommending EBIs and provided public funds for EBIs. Across systems, other facilitators of scale-up were creating EBIs that are ready for scale-up, public awareness of and support for EBIs, community engagement and capacity to implement EBIs, leadership support for EBIs, a skilled workforce capable of delivering EBIs, and data monitoring and evaluation capacity. It was concluded that the following actions are needed to significantly increase EBI scale-up in public systems: (1) provide more public policies and funding to support the creation, testing, and scaling up of EBIs; (2) develop and evaluate specific frameworks that address systems level barriers impeding EBI scale-up; and (3) promote public support for EBIs, community capacity to implement EBIs at scale, and partnerships between community stakeholders, policy makers, practitioners, and scientists within and across systems.

Academic Achievement and Drug Abuse Risk Assessed Using Instrumental Variable Analysis and Co-relative Designs.

Importance: Low academic achievement (AA) in childhood and adolescence is associated with increased substance use. Empirical evidence, using longitudinal epidemiologic data, may provide support for interventions to improve AA as a means to reduce risk of drug abuse (DA). Objective: To clarify the nature of the association between adolescent AA and risk of DA by using instrumental variable and co-relative analysis designs. Design, Setting, and Participants: This study, assessing nationwide data from individuals born in Sweden between 1971 and 1982, used instrumental variable and co-relative analyses of the association between AA and DA. The instrument was month of birth. Co-relative analyses were conducted in pairs of cousins (263 222 pairs), full siblings (154 295), and monozygotic twins (1623) discordant for AA, with raw results fitted to a genetic model. The AA-DA association was modeled using Cox regression. Data analysis was conducted from October 2017 to January 2018. Exposures: Academic achievement assessed at 16 years of age (for instrumental variable analyses), and estimated discordance in AA in pairs of monozygotic twins (for co-relative analyses). Main Outcomes and Measures: Drug abuse registration in national medical, criminal, or pharmacy registries. Results: This instrumental variable analysis included 934 462 participants (478 341 males and 456 121 females) with a mean (SD) age of 34.7 (4.3) years at a mean follow-up of 19 years. Earlier month of birth was associated with a linear effect on AA, with the regression coefficient per month equaling -0.0225 SDs (95% CI, -0.0231 to -0.0219). Controlling for AA, month of birth had no association with risk of DA (hazard ratio [HR], 1.000; 95% CI, 0.997-1.004). Lower AA had a significant association with risk of subsequent DA registration (HR per SD, 2.33; 95% CI, 2.30-2.35). Instrumental variable analysis produced a substantial but modestly attenuated association (HR, 2.04; 95% CI, 1.75-2.33). Controlling for modest associations between month of birth and parental educational status and DA risk reduced the association to a HR of 1.92 (95% CI, 1.67-2.22). The genetic model applied to the results of co-relative analyses fitted the observed data well and estimated the AA-DA association in monozygotic twins discordant for AA to equal a HR of 1.79 (95% CI, 1.64-1.92). Conclusions and Relevance: Two different methodological approaches with divergent assumptions both produced results consistent with the hypothesis that the significant association observed between AA at 16 years of age and risk of DA into middle adulthood may be causal. These results provide empirical support for efforts to improve AA as a means to reduce risk of DA.

Varying Susceptibility of the Female Mammary Gland to In Utero Windows of BPA Exposure.

In utero exposure to the endocrine disrupting compound bisphenol A (BPA) is known to disrupt mammary gland development and increase tumor susceptibility in rodents. It is unclear whether different periods of in utero development might be more susceptible to BPA exposure. We exposed pregnant CD-1 mice to BPA at different times during gestation that correspond to specific milestones of in utero mammary gland development. The mammary glands of early-life and adult female mice, exposed in utero to BPA, were morphologically and molecularly (estrogen receptor-α and Ki67) evaluated for developmental abnormalities. We found that BPA treatment occurring before mammary bud invasion into the mesenchyme [embryonic day (E)12.5] incompletely resulted in the measured phenotypes of mammary gland defects. Exposing mice up to the point at which the epithelium extends into the precursor fat pad (E16.5) resulted in a nearly complete BPA phenotype and exposure during epithelial extension (E15.5 to E18.5) resulted in a partial phenotype. Furthermore, the relative differences in phenotypes between exposure windows highlight the substantial correlations between early-life molecular changes (estrogen receptor-α and Ki67) in the stroma and the epithelial elongation defects in mammary development. These data further implicate BPA action in the stroma as a critical mediator of epithelial phenotypes.

The cycle of victimization: The relationship between childhood maltreatment and adolescent peer victimization.

Child maltreatment has been demonstrated to have many short- and long-term harmful consequences for victims, but whether or not child abuse is associated with an increased risk of peer victimization during adolescence is unclear. This study analyzed prospective data from 831 children and parents participating in the Longitudinal Studies on Child Abuse and Neglect (LONGSCAN) to investigate the relationships between child physical and sexual abuse and adolescent victimization by peers, as well as the potential for gender to moderate these relationships. Results from ordinal logit regression models indicated that children who were physically abused prior to age 12, based on official reports, parent reports, and child reports, had a greater risk of experiencing more intimidation and physical assault by peers at age 16. Having a history of sexual abuse predicted more physical assault but not intimidation. There was no evidence that gender moderated these relationships; in all cases, the relationship between abuse and revictimization was similar for boys and girls. The findings emphasize the need to provide victims of abuse with assistance to help prevent a cycle of victimization.

How Do Family-Focused Prevention Programs Work? A Review of Mediating Mechanisms Associated with Reductions in Youth Antisocial Behaviors.

The development and evaluation of family-focused preventive interventions has grown significantly in recent decades, but the degree to which these interventions produce anticipated improvements in the family environment, and the extent to which such changes are associated with reductions in youth antisocial behaviors (ASB), is unclear. This article seeks to answer these questions by reviewing evidence from tests of mediation conducted in evaluations of family-focused interventions. Interventions are drawn from family-focused interventions rated as Model Plus, Model, or Promising on the Blueprints for Healthy Youth Development Web site ( http://www.colorado.edu/cspv/blueprints/ ) based on evidence of their effectiveness in reducing child externalizing behaviors, substance use, and/or delinquency. Of the 19 such interventions listed on Blueprints, seven programs (37 %) were evaluated using mediation analyses which met study criteria. Two-thirds (67 %) of these analyses indicated significant improvements in the targeted family processes for intervention versus control group participants. Over half (62 %) of all tests of mediation were statistically significant and indicated that improvements in the family environment were associated with reductions in ASB. The results support prior theoretical and empirical literature identifying the family as an important context for preventing ASB and promoting healthy youth development. The findings also provide information that can be used to refine current family-focused interventions in order to increase their efficiency and potency, and to develop new interventions in order to expand the number and types of families who can benefit from such services.