Delinquency between siblings: A meta-analysis

Abstract

Siblings may have as much impact on delinquency as peers and parents. To determine the degree of impact, a meta-analysis was performed on studies investigating delinquency in siblings. A literature review identified 26 non-redundant studies on sibling delinquency and 36 unique samples of sibling pairs and children who estimated delinquency in a sibling or in their sibling network. A medium pooled effect size was obtained, which decreased only slightly when the analysis was restricted to longitudinal estimates. There was a fair amount of heterogeneity in the results but only two out of 21 moderator effects were significant. One moderator effect indicated that direct reports of delinquency from a sibling produced a significantly stronger effect than when perceived sibling delinquency estimates were used, and the other indicated that longitudinal studies performed in the United States generated a higher pooled effect size than longitudinal studies conducted outside the United States. There was also greater concordance for delinquency in same-sex siblings than in mixed-sex dyads and a non-significant trend in longitudinal studies showing transmission progressing from older to younger siblings. These results suggest that siblings are a salient risk factor for delinquency and that they are potentially important in the development of offending behavior. • Literature review identified 26 non-redundant studies on sibling delinquency. • 36 unique samples of sibling pairs subjected to meta-analysis • Modest to moderate pooled effect size using either concurrent or prospective data • Greater concordance for delinquency in same-sex siblings than in mixed-sex dyads • Sibling delinquency appears to be a salient risk factor for delinquency.