A large scale analysis of the JETS programme using a model of clinically significant change

Purpose: The study investigates the effectiveness of JETS, a Cognitive Behavioural Programme, designed for young people (16-18 years) in custody. The research explores group and individual level change against short and long term outcomes, including reconviction and re-imprisonment. Associations between outcomes are investigated, as is the role of individual response to treatment. Method: JETS participants were compared with a custody comparison group on short term measures that are: Malevolent Aggression, Social Anxiety, Social Self Esteem, Impulsivity, Venturesomeness, Empathy, and Locus of Control. Individual change on each measure was explored using a model of Clinically Significant Change (Jacobson and Truax, 2001). Reconviction and re-imprisonment rates at both 12 and 24 months were investigated, including analysis of days post release. Interactions between response to treatment and reconviction were explored. Results: JETS participants improved significantly better than the comparison group on Malevolent Aggression and Locus of Control. JETS participants showed significantly higher levels of Reliable Change and Cut off on Locus of Control as well as being significantly more likely to achieve Reliable Change on 1 or more of the short term measures. JETS participants were significantly less likely to be reconvicted or receive a sentence of imprisonment at 12 and 24 months post release. They also achieve significantly longer periods of release prior to reconviction or re-imprisonment over both 12 and 24 months, whilst controlling for risk. No associations between change on short term measures and reconviction or re-imprisonment were identified. Associations between Time 2 scores on Impulsivity Locus of Control and Social Anxiety and measures of reoffending were observed over both 12 and 24 months periods. Conclusions: This research supports JETS as an effective Offending Behaviour intervention for young people in custody. It demonstrates the importance of multiple level evaluations for both treatment and research purposes. Implications for treatment are discussed.