American Psychologist, Vol 80(6), Sep 2025, 910-927; doi:10.1037/amp0001405
For over 30 years, general cognitive-behavioral programs have contributed to the rehabilitation services offered within His Majesty’s Prison and Probation Service in England and Wales. There is an extensive body of international evidence that demonstrates the effectiveness of such interventions as a correctional strategy. However, there is widespread variability of program effects associated with the standards of implementation. Over the last 3 decades, British researchers have produced a steady output of quasi-experimental program evaluations that have contributed to the evidence base. The most recent additions are some of the largest and most rigorous available worldwide. This review documents those evaluations and provides a meta-analysis that statistically aggregates the effects of programs delivered in His Majesty’s prisons in England and Wales. We suggest there is sufficient evidence from evaluations of acceptable scientific rigor to conclude that general cognitive-behavioral programs delivered in prisons during the last decade and a half (circa 2006 to 2019) have had a small statistically significant mean reductive effect on general reoffending (odds ratio = 0.91). Program characteristics and implementation factors, including program dose, the scale of service delivery and program integrity, are discussed as possible factors associated with the size of the effect. (PsycInfo Database Record (c) 2025 APA, all rights reserved)