Background: There is a lack of knowledge about specific effective ingredients of prevention programs for youth at risk for
persistent delinquent behavior. The present study combines findings of previous studies by examining the effectiveness of
programs in preventing persistent juvenile delinquency and by studying which particular program, sample, and study characteristics
contribute to the effects. Information on effective ingredients offers specific indications of how programs may be improved
in clinical practice.
Method: A literature search in PsychINFO, ERIC, PubMed, Sociological Abstracts, Criminal Justice
Abstracts, and Google Scholar was performed. Only (quasi)experimental studies and studies that focused on adolescents at risk
for (persistent) delinquent behavior were included. Multilevel meta-analysis was conducted on 39 studies (N = 9,084). Participants’
ages ranged from 6 to 20 years (M = 14 years, SD = 2.45).
Results: The overall effect size was significant and small in
magnitude (d = 0.24, p < .001). Behavioral-oriented programs, focusing on parenting skills training, behavioral modeling,
or behavioral contracting yielded the largest effects. Multimodal programs and programs carried out in the family context
proved to be more beneficial than individual and group-based programs. Less intensive programs yielded larger effects.
Prevention programs have positive effects on preventing persistent juvenile delinquency. In order to improve program effectiveness,
interventions should be behavioral-oriented, delivered in a family or multimodal format, and the intensity of the program
should be matched to the level of risk of the juvenile.