Young offenders in forensic institutions in the Netherlands after committing serious crimes: Contribution of mandatory treatment and reduction of reincarceration.

Outcomes of mandatory treatment in this group of serious young offenders have not previously been studied in a rigorous pre-post intervention study design. We found evidence of an overall tendency to improvement over time in mental state and social skills, reflected by risk assessment scale scores. Continued substance use problems while incarcerated and continuing social skills deficits were most strongly associated with reincarceration suggests a possible need for review of these areas in the PIJ-measure programme. Results contribute to knowledge about risk assessment, treatment and preventions of harms by serious young offenders and may inform evidence-based policies and practices in the Netherlands and beyond.