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Objectives We assessed the effectiveness of a 5-year trial of a comprehensive school-based program designed to prevent substance use, violent behaviors, and sexual activity among elementary-school students. Methods We used a matched-pair, cluster-randomized, controlled design, with 10 intervention schools and 10 control schools. Fifth-graders (N=1714) self-reported on lifetime substance use, violence, and voluntary sexual activity. Teachers of participant students reported on student (N=1225) substance use and violence. Results Two-level random-effects count models (with students nested within schools) indicated that student-reported substance use (rate ratio [RR]=0.41; 90% confidence interval [CI]=0.25, 0.66) and violence (RR=0.42; 90% CI=0.24, 0.73) were significantly lower for students attending intervention schools. A 2-level random-effects binary model indicated that sexual activity was lower (odds ratio=0.24; 90% CI=0.08, 0.66) for intervention students. Teacher reports substantiated the effects seen for student-reported data. Dose-response analyses indicated that students exposed to the program for at least 3 years had significantly lower rates of all negative behaviors. Conclusions Risk-related behaviors were substantially reduced for students who participated in the program, providing evidence that a comprehensive school-based program can have a strong beneficial effect on student behavior.

This paper reports the effects of a comprehensive elementary school-based social-emotional and character education program on school-level achievement, absenteeism, and disciplinary outcomes utilizing a matched-pair, cluster randomized, controlled design. The Positive Action Hawai‘i trial included 20 racially/ethnically diverse schools (mean enrollment = 544) and was conducted from the 2002-03 through the 2005-06 academic years. Using school-level archival data, analyses comparing change from baseline (2002) to one-year post trial (2007) revealed that intervention schools scored 9.8% better on the TerraNova (2nd ed.) test for reading and 8.8% on math; 20.7% better in Hawai‘i Content and Performance Standards scores for reading and 51.4% better in math; and that intervention schools reported 15.2% lower absenteeism and fewer suspensions (72.6%) and retentions (72.7%). Overall, effect sizes were moderate to large (range 0.5-1.1) for all of the examined outcomes. Sensitivity analyses using permutation models and random-intercept growth curve models substantiated results. The results provide evidence that a comprehensive school-based program, specifically developed to target student behavior and character, can positively influence school-level achievement, attendance, and disciplinary outcomes concurrently.

This study examined the effects of the Positive Action (PA) programme in Chicago Public Schools on problem behaviours among a cohort of elementary school students from grade three through grade five. Using a matched-pair, randomised control design with 14 elementary schools, approximately 510 fifth-graders self-reported lifetime substance use, serious violence-related behaviour, and current bullying and disruptive behaviours. Three-level (i.e. students nested within schools within school pairs) overdispersed Poisson models were used to examine programme effects on the number of items endorsed for each of the four outcomes. Findings indicated that students in the intervention endorsed 31% fewer substance use behaviours (incidence rate ratio [IRR] = 0.69), 37% fewer violence-related behaviours (IRR = 0.63) and 41% fewer bullying behaviours (IRR = 0.59), respectively, compared to students in the control schools. Reduction in reported disruptive behaviours was of a similar magnitude (27%, IRR = 0.73), but was not statistically significant. These results replicate findings of an earlier randomised trial of the PA programme and extend evidence of its effectiveness to youth attending large urban school systems.

Previous research has shown that people err when making decisions aided by probability information. Surprisingly, there has been little exploration into the accuracy of decisions made based on many commonly used probabilistic display methods. Two experiments examined the ability of a comprehensive set of such methods to effectively communicate critical information to a decision maker and influence confidence in decision making. The second experiment investigated the performance of these methods under time pressure, a situational factor known to exacerbate judgmental errors. Ten commonly used graphical display methods were randomly assigned to participants. Across eight scenarios in which a probabilistic outcome was described, participants were asked questions regarding graph interpretation (e.g., mean) and made behavioral choices (i.e., act; do not act) based on the provided information indicated that decision-maker accuracy differed by graphical method; error bars and boxplots led to greatest mean estimation and behavioral choice accuracy whereas complementary cumulative probability distribution functions were associated with the highest probability estimation accuracy. Under time pressure, participant performance decreased when making behavioral choices.