We conducted a meta-analysis of 17 studies that tested for an association between grandparental survival and grandchild survival in patrilineal populations. Using two different methodologies, we found that the survival of the maternal grandmother and grandfather, but not the paternal grandmother and grandfather, was associated with decreased grandoffspring mortality. These results are consistent with the findings of psychological studies in developed countries (Coall and Hertwig Behavioral and Brain Sciences 33:1-59, 2010). When tested against the predictions of five hypotheses (confidence of paternity; grandmothering, kin proximity, grandparental senescence, and local resource competition), our meta-analysis results are most in line with the local resource competition hypothesis. In patrilineal and predominantly patrilocal societies, the grandparents who are most likely to live with the grandchildren have a less beneficial association than those who do not. We consider the extent to which these results may be influenced by the methodological limitations of the source studies, including the use of retrospective designs and inadequate controls for confounding variables such as wealth.

This meta-analysis examines more than twenty-five years of evidence to determine whether participation in school-based conflict resolution education (CRE) contributes to reduced antisocial behaviors among youth in kindergarten through twelfth grade in U.S. schools. Evidence from thirty-six studies, representing 4,971 students, shows improvements in antisocial behaviors in CRE participants compared to control groups ( Effect Size ϭ .26), with larger effects observed during midadolescence ( ES ϭ .53) and early adolescence ( ES ϭ .22) compared to middle childhood ( ES ϭ .06). Improvements in antisocial behavior outcomes attributable to CRE are significant in both practical and statistical terms and are similar for different CRE program approaches.

No abstract

No abstract

No abstract