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Updated: Jun 19, 2026

Problem-Solving Before Instruction (PS-I): A Protocol for Assessment and Intervention in Students with Different Abilities
Published on: September 11, 2021
An experimental evaluation of the All Stars prevention curriculum in a community after school setting
Denise C Gottfredson1, Amanda Cross, Denise Wilson
1Department of Criminology and Criminal Justice, University of Maryland, 2220D LeFrak Hall, College Park, MD 20742-8235, USA. dgottfredson@crim.umd.edu
Abstract:
This study tested the effectiveness of a prevention curriculum, All Stars, as implemented in a year-long school-based after school program and provides an independent replication of the effects of All Stars on targeted mediators and problem behaviors using an experimental methodology. Middle school students (N = 447) who registered for the after school program were randomly assigned to the experimental or control condition. The sample included approximately equal proportions of males and females, was 70% African American, and 59% of the students received subsidized meals at school. All Stars was delivered with reasonable integrity to the program design, although with lower quality than reported in earlier efficacy trials. However, actual student exposure to the program was lower than expected due to low levels of attendance in the after school program. Students who ever attended received an average of 16 h of All Stars instruction. Results showed no differences between the treatment and control students at post-test on any of the outcomes or mediators. Further, no positive effects were found for youths receiving higher dosage, higher quality program delivery, or both. Insufficient time to achieve high quality implementation in the after school context and potential deviancy training are suggested as reasons for the failure to replicate positive program effects.
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