Meta-Analysis Snapshot
|
Literature Coverage Dates |
Number of Studies |
Number of Study Participants |
Meta Analysis 1 |
1975-2015 |
41 |
9382 |
Meta Analysis 1Piquero and colleagues (2016) updated an earlier meta-analysis by Piquero, Jennings, and Farrington (2010) on the effects of early self-control improvement programs on increasing self-control and reducing delinquency/crime of children. Screening was conducted from January 2010 through September 2015, extending the original analysis period of 1975 to 2009.
Studies were included if they 1) used randomized controlled experimental designs; 2) included self-control as a major component of the intervention; 3) included participants aged 10 years and younger (or the mean age was no greater than 10 years at the start of the intervention); 4) included at least one child-based outcome measure of self-control such as the Kansas Reflection-Impulsivity Scale for Preschoolers (Wright 1971), the Kendall and Wilcox Self-Control Rating Scale (Kendall and Wilcox 1979), Burks’ (1996) Behavior Rating Scale, and/or behavioral outcome measures of general problem behaviors, such as antisocial behavior and delinquency, from the Child Behavior Checklist (Achenbach and Edelbrock 1983) or the Eyberg Child Behavior Inventory (Funderburg and Eyberg 1989); and 5) made available adequate posttest data to calculate an effect size, if not provided. The search included published and unpublished reports available in English with no timeframe or geographic restrictions. Keyword searches were done for abstracts across several online databases, and hand searches were conducted with reputable journals in the areas of criminology, criminal justice, policing, public policy, psychology, psychiatry, and child development.
This analysis included 41 randomized controlled trial studies, updating the original analysis with 7 additional eligible studies. The 41 studies had a total sample size of 9,382 children and adolescents. A total of 53 self-control effect sizes and 36 delinquency effect sizes were calculated in this analysis. Studies included in the analysis were predominately published in journals, took place in a number of states across the country (e.g., Florida, Georgia, Hawaii, Illinois, Indiana, Kentucky, Maryland, Massachusetts, Michigan, New Mexico, New York, North Carolina, Oregon, Pennsylvania, Tennessee, Washington, and Wisconsin), and were delivered in a school setting. The study samples were mostly male, white, high-risk, and from low-income populations. Participants’ ages ranged from 2 to 10 years.
A random effects analysis was used to estimate overall mean effect size. Cohens d was used to calculate the standardized mean difference effect sizes. When studies did not provide a Cohen’s d effect size estimate, the data that were provided was transformed into a Cohen’s d. Hedges g was applied correcting for small sample sizes small samples. Inverse variance weights were used to give greater weight to the effect sizes estimated with more precision. All meta-analytic results were estimated using Comprehensive Meta-Analysis (CMA) software, Version 2.