Research Findings - Prevention Research
Comprehensiveness of Substance Use Prevention Programs in U.S. Middle Schools
This study assessed how current practice in middle school substance use prevention programs compares to seven recommended guidelines adapted from the Centers for Disease Control and Prevention's guidelines for school-based tobacco use prevention programs. Substance use prevention practice was analyzed using data from a 1999 mailed survey of a nationally representative sample of 1,496 public and private schools with middle school grades that reported having a substance use prevention program. An estimated 64 percent of schools met four or more of the recommendations for school-based substance use prevention practice; 4 percent met all seven recommendations. Of the seven, schools were most likely to report having and enforcing substance use prevention policies (84 percent), and least likely to report training teachers in substance use prevention (18 percent). More recommendations were implemented by schools with the following characteristics than by those without them: they were public, had larger enrollments, greater perceived availability of resources, greater school board and parental support for substance use prevention, and had hired a school substance use prevention coordinator. Additional resources may be needed to increase the prevalence of comprehensive substance use prevention programs in U.S. middle schools. Wenter, D.L., Ennett, S.T., Ribisl, K., Vincus, A.A., Rohrbach, L., Ringwalt, C.L., and Jones, S.M. Journal of Adolescent Health, 30(6), pp. 457-464, 2003.
Outcomes of the Minnesota DARE PLUS Project
In the past, the Drug Abuse Resistance Education (DARE) has been the most widely used drug use prevention program in elementary schools. Several evaluations have shown the program's lack of effectiveness; other evaluations of the DARE curriculum have reported short-term changes in cigarette smoking that have been modest in size. The Minnesota DARE PLUS Project was designed to capitalize on the successful elements of DARE and also provide additional, complementary components based on state-of-the-art prevention strategies. DARE PLUS curriculum focuses on middle/junior high school level, and is designed to reduce tobacco, alcohol and marijuana use, and violent behavior among 7th and 8th grade students. The evaluation study of DARE PLUS involved 24 middle and junior high schools in Minnesota that were matched on socio-economic measures, drug use, and size, and were randomly assigned to three conditions: 1) DARE; 2) DARE PLUS, and 3) delayed DARE PLUS control. The principal outcomes of the study were measured by self-administered questionnaires. Differences between the three conditions were tested using a three-level, linear, random coefficients model. DARE PLUS was found to significantly improve the DARE middle/junior high curriculum, and was an effective intervention for reducing alcohol, tobacco, and multi-drug use and victimization among adolescent boys. However, DARE PLUS did not demonstrate similar effects among adolescent girls. The gender differences in outcomes need further exploration. Perry, C.L., Komro, K.A., Veblen-Mortenson, S., Bosma, L.M., Farbakhsh, K., Munson, K.A., Stigler, M.H., and Lytle, L.A. A Randomized Controlled Trial of the Junior High DARE and DARE PLUS programs. Archives of Pediatrics and Adolescent Medicine, 157, pp. 178-184, 2003.
Positive Support for the Theoretical Model in the Coping Power Program
This study tests the contextual social-cognitive model, which has served as the basis for the Coping Power program. That program involves an indicated preventive intervention with at-risk preadolescent boys at the time of transition from elementary to middle school. The contextual social-cognitive (CSC) model assumes that (a) aggressive children have distortions in their social-cognitive appraisals and deficiencies in their social problem solving skills and (2) their parents have deficiencies in parenting behaviors. To test this model, particularly the assumption that changes in CSC processes can impact later adolescent outcomes and that these outcomes are mediated through intervention-produced changes at one-year post-intervention follow up, 183 boys were identified as being at risk on the basis of fourth grade and fifth grade teachers' ratings of children's aggressive and disruptive behaviors. Subsequently, the interventions were delivered at the end of elementary school and the beginning of middle school. The intervention effect on delinquency, substance use, and school behavior outcomes was at least partially mediated through intervention-produced changes in the child and parent variables that were targets for the intervention. These analyses testing the model at one-year follow up assessment provided unique support for the assumptions in the CSC model. Changes in the mediating processes, even among high-risk boys, have a meaningful impact on later negative outcomes. Lochman, J.E., and Wells, K.C. Contextual Social-Cognitive Mediators and Child Outcome: A Test of the Theoretical Model in the Coping Power Program. Development and Psychopathology, 14(4), pp. 945-967, 2002.
Effects of The Coping Power Program
This study evaluates the effects of both a universal and an indicated preventive intervention. Children were identified as being at risk on the basis of 4th-grade teachers' ratings of children's aggressive and disruptive behaviors. Interventions were delivered during the 5th- and 6th-grade years. Children were randomly assigned to the Coping Power (indicated) intervention, the universal intervention, the combined Coping Power plus universal intervention, or a control condition. The Coping Power program included child and parent components. Results indicated that all three intervention conditions produced relatively lower rates of substance use at post-intervention than did the control condition. The interventions also produced effects on three of the four predictor variable domains: children's social competence and self-regulation and parents' parenting skills. Lochman, J.E., and Wells, K.C. The Coping Power Program at the Middle-School Transition: Universal and Indicated Prevention Effects. Psychology of Addictive Behaviors, 16(4), pp. S40-S54, 2002.
Three-Year Outcomes of the Early Risers Longitudinal Prevention Trial
This study evaluated the effects of participation following a 3-year preventive intervention trial targeting elementary school children with early-onset aggressive behavior. The Early Risers intervention model includes two core components: CORE, a coordinated set of school-centered interventions that target key developmental domains underlying risk and protection in young children and FLEX, a risk-adjusted family-focused intervention delivered through home visitation to foster parenting skills. Intent-to-treat analyses revealed that compared with controls, program participants showed greater gains in social skills, academic achievement, and parent discipline, with mean scores in the normative range on the latter two constructs. As-intended participation in the FLEX Family Program, which included separate parent and child education and skills-training groups, was associated with improved parent discipline practices and gains in children's social skills, with level of child aggression moderating gains in academic achievement. Recommended level of FLEX family support contact time was associated with gains in academic achievement, concentration problems, and social skills, with parents of severely aggressive children showing greater reductions in parent distress. August, G.J., Hektner, J.M., Egan, E.A., Realmuto, G.M. and Bloomquist, M.L. The Early Risers Longitudinal Prevention Trial: Examination of 3-Year Outcomes in Aggressive Children with Intent-to-Treat and As-Intended Analyses. Psychology of Addictive Behaviors, 16(4), pp. S27-S39, 2002.
Findings from the Raising Healthy Children Social Development Intervention
This study examined results of a comprehensive, multifaceted longitudinal school-based prevention program called Raising Healthy Children (RHC). RHC focuses on enhancing protective factors with the goal of promoting positive youth development, reducing identified risk factors and preventing adolescent problem behaviors. Participants included 938 first or second graders who were enrolled in 10 area schools in the Pacific Northwest and randomly assigned to the RHC or control condition. Analyses were conducted 18 months after implementation and focused on academic and behavioral outcomes in the school environment. Results using hierarchical linear modeling showed that RHC students, compared to their peers who did not receive the intervention, had significantly higher teacher-reported academic performance and a stronger commitment to school. RHC students showed a significant decrease in antisocial behaviors and an increase in social competency compared to control peers. Regression results from parent-reported outcomes also showed that RHC students had higher academic performance and a stronger commitment to school. Catalano, R.F., Mazza, J.J., Harachi, T.W., Abbott, R.D., Haggerty, K.P. and Fleming, C.B. Raising Healthy Children Through Enhancing Social Development in Elementary School: Results after 1.5 years. Psychology of Addictive Behaviors 16(2), pp. 129-134, 2003.
Peer Influence and Prevention of Problem Behavior
Research shows that deviant peer influence is related to the escalation of various problem behaviors such as substance use, delinquent behavior and violence. The goal of this research was to examine the effects of a family-centered prevention strategy on deviant peer affiliation. The investigators hypothesized that the Adolescent Transitions Program (ATP) would significantly reduce growth in deviant peer affiliation from the beginning of sixth grade to the beginning of ninth grade and that the reduced growth in deviant peer involvement would be correlated with the intensity of the parents' contact with the intervention. The Adolescent Transitions Program involves a 6-week classroom curriculum for all intervention youth, a Family Check-Up component to improve the family management in families identified by a teacher as potentially at-risk, and additional preventive strategies, such as family therapy and brief consultations, for families with motivation and need for assistance. This intervention was administered through a "Family Resource Center" at the school. Six hundred seventy-one youth and their families were recruited to participate from a diverse metropolitan community. Using latent growth analysis, the growth in deviant peer involvement for intervention youth was reliably less than that of the control group. In addition, the results showed that the extent to which parents accessed the family resource center mediated growth in deviant peer affiliation. Dishion, T.J., Bullock, B.M., and Granic, I. Pragmatism in Modeling Peer Influence: Dynamics, Outcomes, and Change Processes. Development and Psychopathology, 14, pp. 969-981, 2002.
Test of the Early-Starter Model of the Development of Serious Conduct Problems
The Fast Track prevention trial was used to test hypotheses from the Early-Starter Model of the development of chronic conduct problems. The researchers randomly assigned 891 high-risk first-grade boys and girls (51 percent African American) to receive or not receive the long-term Fast Track preventive intervention. After four years, outcomes were assessed through teacher ratings, parent ratings, peer nominations, and child self-report. The positive effects of assignment to intervention were evident in teacher and parent ratings of conduct problems, peer social preference scores, and association with deviant peers. Assessments of proximal goals of intervention (e.g., reduced hostile attributional bias, harsh parental discipline, and aggressive behavior at home and school; improved problem-solving skills and pro-social behavior), collected after third grade were found to partially mediate these effects. The findings are interpreted as consistent with developmental theory. Bierman, K.L., Coie, J.D., Dodge, K.A., Greenberg, M.T., Lochman, J.E., McMahon, R.J., and Pinderhughes, E.E. Using the Fast Track Randomized Prevention Trial to Test the Early-Starter Model of the Development of Serious Conduct Problems. Development and Psychopathology, 14, pp. 925-943, 2002.
Generalizability of the Social Development Model
The social development model is a theory of behavior that has proven useful in explaining the etiology of delinquency, violence, and substance use among adolescents as well as early antisocial behavior among preadolescents. To test the model's generalizability across gender and income groups, a section of the model representing prosocial influences in the etiology of problem behavior was compared for girls and boys and for children from low-income families and non low-income families. Using a sample of 851 elementary school-aged youth from the Raising Healthy Children study, multiple group structural equation modeling was used to assess differences across groups in both measurement of model constructs and hypothesized structural paths between constructs. For both sets of comparisons, overall similarity was found in both measurement and structural models, indicating the robustness of the social development model for different groups. While some studies of differences in the effects of social/interactional variables on problem behavior in adolescence have shown differences by gender and ethnicity, these findings indicate that generally the protective paths from early social skills and family socialization to problem behavior in the elementary school period appear to operate in much the same way in different gender and income groups. Fleming, C.B., Catalano, R.F., Oxford, M.L., and Harachi, T.W. A Test of Generalizability of the Social Development Model Across Gender and Income Groups with Longitudinal Data from the Elementary School Development Period. Journal of Quantitative Criminology, 18(4), pp. 423-439, 2002.
Protective Aspects of American Indian Culture
American Indian youth have notably high rates of use of alcohol and certain illicit substances, yet prevention efforts for this population have been limited. This study examines whether and in what ways differences in ethnic and cultural identities among American Indian youth relate to their drug use norms. Four hundred thirty-four seventh graders from a large southwestern U.S. city who self-identified as American Indian provided self-reports of their norms in use of alcohol, tobacco, marijuana, and other drugs as well as the strength of their ethnic self-identities. Regression analysis indicated that ethnic pride was predictive of some anti-drug norms. For example, students who had a more intense sense of ethnic pride were more likely to report that it was not OK for someone their age to use alcohol, cigarettes, or marijuana. Intragroup ethnic diversity and speaking English only at home and with friends were unrelated to drug norms when other predictors were controlled, and there were few differences by gender, socioeconomic status, or age. Kulis, S., Napoli, M., and Marsiglia, F.F. Ethnic Pride, Biculturalism, and Drug Use Norms of Urban American Indian Adolescents. Social Work Research, 26(2), pp. 101-112, 2002.
Parent Figure Transitions, Delinquency, and Drug Abuse
Children of substance abusing parents have an elevated risk for experiencing disruptions in household composition, including changes in primary caretakers. This study investigated whether changes in caretakers, also called "parent figure transitions" predicted the likelihood of delinquency and drug use among a sample of youth with parents receiving methadone treatment for opiate addiction. A sample of 67 youth was derived from the Focus on Families program, a family-based intervention study to prevent substance abuse in children of opiate-addicted parents. For this analysis, 67 children ages 9-14 were interviewed (mean age=11.4 years at baseline; 13.8 years at final interview). Controlling for baseline delinquency, child characteristics, family conflict, parental depression, and parent criminal history, a greater number of parenting disruptions during the longitudinal study period was associated with a higher probability of delinquent behavior. Gender moderated the effect of parent figure transitions in a parallel analysis for drug use. After accounting for baseline drug use and other confounders, only adolescent females had a higher likelihood of drug use as the number of family disruptions increased. A subgroup of youth who experienced tremendous family instability and had no single consistent parent figure during the study were at extreme risk for delinquent behavior. Keller, T.E., Catalano, R.F., Haggerty, K.P., and Fleming, C.B. Parent Figure Transitions and Delinquency and Drug Use Among Early Adolescent Children of Substance Abusers. American Journal of Drug and Alcohol Abuse, 28(3), pp. 399-427, 2002.
Alienation, Aggression and Sensation Seeking Predict Adolescent Use of Violent Media Content
Use of violent media content by adolescents has become an even greater matter of concern following the Columbine shootings. This study examined predictors of various types of self-reported use of violent media content by 8th graders (N=3,127) from 20 schools around the U.S. Hierarchical regression analyses indicate that gender, sensation seeking, aggression, and frequency of Internet use make relatively strong contributions to explaining the use of media content based on a composite measure of use of violent media content (i.e., use of action films, video/computer games, and violence-oriented Internet site use), as well as on a measure of violent website content use. Alienation variables contribute significantly, albeit modestly, to variance explained in the use of violence-oriented websites but not the composite measure. Alienation from school and family also appears to partially mediate effects of sensation seeking and aggression on use of violent Internet content. These findings suggest the relative importance of traits such as sensation seeking and aggressiveness in predicting use of violent media content in general. In addition, youth who feel alienated from school or family may turn to antisocial media content, particularly websites, as alternatives to antisocial peer groups. However, from a social policy perspective, focusing on such websites may be less effective than intervention strategy directed at alienation factors including schools and family relationships. Slater, M.D. Alienation, Aggression and Sensation Seeking as Predictors of Adolescent Use of Violent Film, Computer and Website Content. Journal of Communication 53(1), pp. 105-121, 2003.
Leisure Time Motivation Scale for Adolescents
Understanding and measuring motivation can be important in developing and testing prevention interventions for youth. A new self- report measure of adolescent free-time motivation based on self-determination theory (Ryan & Deci, 2000) has been developed. The scale measures five forms of motivation (amotivation, external, introjected, identified, and intrinsic motivation), and is appropriate for use with young adolescents (ages 12-15). Using confirmatory factor analysis, examination of each of the motivation subscales indicated minimally acceptable levels of fit. The test of the overall model without modification was also minimally acceptable. The deletion of two items improved the fit and provided preliminary evidence of the validity of the overall scale. However, future replication of this finding is needed. Baldwin, C.K., and Caldwell, L.L. Leisure Time Motivation Scale for Adolescents. Journal of Leisure Research, 35, pp. 129-151, 2003.
Adding Missing-Data-Relevant Variables to FIML-Based Structural Equation Models
Conventional wisdom in missing data research dictates adding variables to the missing data model when those variables are predictive of (a) missingness and (b) the variables containing missingness. However, it has recently been shown that adding variables that are correlated with variables containing missingness, whether or not they are related to missingness, can substantially improve estimation (by reducing bias and increasing efficiency). Including large numbers of these "auxiliary" variables is straightforward for researchers who use multiple imputation. However, what is the researcher to do if one of the full-information maximum likelihood (FIML) structural equation model (SEM) procedures is the analysis of choice? This article suggests two models for SEM analysis with missing data, and presents simulation results to show that both models provide estimation that is clearly as good as analysis with the expectation maximization (EM) algorithm, and by extension, multiple imputation. One of these models, the saturated correlates model, also provides good estimates of model fit. Graham, J.W. Adding Missing-Data-Relevant Variable to FIML-Based Structure Models. Structural Equation Modeling, 10(1), pp. 80-100, 2003.
Mediation Designs for Tobacco Prevention Research
This article describes research designs and statistical analyses to investigate how tobacco prevention programs achieve their effects on tobacco use. A theoretical approach to program development and evaluation useful for any prevention program guides the analysis. The theoretical approach focuses on action theory for how the program affects mediating variables and on conceptual theory for how mediating variables are related to tobacco use. Information on the mediating mechanisms by which tobacco prevention programs achieve effects is useful for the development of efficient programs and provides a test of the theoretical basis of prevention efforts. Examples of the potential mediating mechanisms are described including mediated effects through attitudes, social norms, beliefs about positive consequences, and accessibility to tobacco. Prior research provides evidence that changes in social norms are a critical mediating mechanism for successful tobacco prevention. Analyses of mediating variables in single group designs with multiple mediators are described as are multiple group randomized designs which are the most likely to accurately uncover important mediating mechanisms for successful tobacco prevention. More complex dismantling and constructive designs also are described and illustrated using current findings from tobacco research. Mediation analysis for categorical outcomes and more complex statistical methods are discussed. MacKinnon, D.P., Taborga, M.P., and Morgan-Lopez, A.A. Drug and Alcohol Dependence, 68, pp. 69-83, 2002.
A Comparison of Methods to Test Mediation and Other Intervening Variable Effects
A Monte Carlo study compared 14 methods to test the statistical significance of the intervening variable effect. An intervening variable (mediator) transmits the effect of an independent variable to a dependent variable. The commonly used R.M. Baron and D.A. Kenny approach has low statistical power. Two methods based on the distribution of the product and two difference-in-coefficients methods have the most accurate Type I error rates and greatest statistical power except in one important case in which Type I error rates are too high. The best balance of Type I error and statistical power across all cases is the test of the joint significance of the two effects comprising the intervening variable effect. Tests of the intervening variable effect are useful because they examine processes by which variables are related. In clinical and community research, such tests are critical for the elucidation of how prevention and treatment programs work. MacKinnon, D.P., Lockwood, C.M., Hoffman, J.M., West, S.G., and Sheets, V. A Comparison of Methods to Test Mediation and Other Intervening Variable Effects. Psychological Methods, 7(1), pp. 83-104, 2002.
Preventive Intervention Implementation in Rural Schools
Interactive prevention programs (i.e., characterized by dynamic instructional processes such as engaging students in classroom discussions, role-plays, and games) have been proven to be more effective in decreasing student problem behaviors than didactic practices. While almost all rural schools provide some programming to address student behavior problems, minimal attention has been paid to the unique features of rural schools that are particularly relevant to training teachers in the delivery of interactive preventive interventions. This paper describes teacher evaluation of a training based on a model proposed by Tortu and Botvin (1989) and the process of implementing the interactive intervention components of the Capable Families and Youth Prevention Project. This study involves the recruitment of thirty-six schools from communities in a rural Midwestern state for a test of the efficacy of school-based and school-based plus family-based substance abuse prevention programs. Teachers who participated in a two-day training completed an evaluation immediately after the training and upon completion of the classroom implementation. Results showed that teachers were confident about their ability to deliver the program following both training and classroom implementation. Lillehoj, C.J., Spoth, R., and Trudeau, L. Rural Teacher Training. Rural Educator, 24(1), pp. 3-12, 2002.
Factors Associated with Regular Marijuana Use Among High School Students: A Long-Term Follow-up Study
The present study investigated whether several behavioral and psychosocial factors measured during early adolescence predicted regular marijuana use 6 years later in a sample of high school students. As part of a school-based survey, 7th-grade students (N=1132) reported levels of alcohol, tobacco, and marijuana use, and were assessed on several domains of psychosocial functioning potentially relevant in the etiology of marijuana use. When students were followed-up in the 12th grade, 14% smoked marijuana on a regular basis (once or more per month). Findings indicated that early cigarette smoking, alcohol use, and alcohol intoxication predicted later regular marijuana use. For boys, early marijuana use increased the odds for later regular marijuana use. Cigarette smoking by friends and siblings during early adolescence also increased the likelihood of later monthly marijuana use. The findings suggest that early prevention programs for adolescent alcohol, tobacco, and/or other drug use may have important preventive effects in terms of potentially more serious levels of marijuana involvement later in adolescence and early adulthood. Griffin, K.W., Botvin, G.J., Scheier, L.M. and Nichols, T.R. Factors Associated with Regular Marijuana Use among High School Students: A Long-Term Follow-up Study. Substance Use & Misuse, 37, pp. 225-238, 2002.