Cognitive Behavioural Therapy
We summarise a systematic review (Lipsey et al., 2007) of the effects of cognitive behavioral programmes for offenders. Cognitive Behavioural Therapy (CBT) aims to reduce offending by helping offenders to change the way they think about, and interact with, the world around them. CBT is the basis of many offender behavior programmes, drawing on well-established theory and practice, and is supported by a substantial body of research dating back to the 1970s (Lipsey et al., 2007). The evidence consistently shows it is one of the most effective approaches to reducing offending and recidivism.
What is it?
Cognitive Behavioural Therapy targets the thoughts and ideas that can sometimes lead to offending behaviour. Criminal offenders frequently display ‘cognitive deficits and distortions’ such as self-justification, misinterpretation of social cues, displacement of blame, a victim mentality, and deficient moral reasoning (Lipsey et al., 2007: 4). This may encourage or produce offending behaviour, for instance in the case of a violent response to provocation that leads to physical assault. CBT challenges these distortions and behaviours directly, through a range of interventions that include cognitive skills training (to highlight and improve distorted thinking); anger management and conflict resolution skills (to create a wider repertoire of responses to external factors), and efforts to challenge offenders’ self-justifications (Lipsey et al., 2007; Friendship et al., 2002).
Should it work?
CBT works on the basis that many of the factors that produce ‘criminal thinking’ are not inherent but are learned behaviours (Lipsey et al., 2007: 4). By explicitly targeting these thoughts and behaviours CBT provides a foundation for Offender Behaviour Programmes, offering a tailored approach and a flexible set of tools. CBT can work with both young and adult offenders; it can be delivered inside or outside of institutional settings, and it can be provided as a stand-alone intervention or as a package of interventions.
Does it work?
Research shows that CBT has significant positive effects on recidivism among young and adult offenders, and can bring about lasting changes in behaviour. The most recent meta-analysis of research studies on CBT (Lipsey et al., 2007) found that participants in these programmes have significantly reduced rates of recidivism compared to other interventions. The review also identified factors related to higher or lower success rates. The review found that those with a higher risk of reoffending experienced the strongest positive results from the process. The authors of the review concluded that this was because the intensive nature of CBT was well suited to offenders with complex needs. The review found that some aspects of CBT were more effective than others: for instance, where programmes provided training on anger-management or improving interpersonal problem solving, the interventions were shown to be more effective than the average. In contrast, where victim impact statements and behaviour modification approaches were used, the interventions were less effective than the average.
The forest plot below shows the effect size distribution, using random effects estimates. The mean odds ratio representing the average effect of intervention was 1.53 (p<.001), indicating that the odds of success (i.e., no recidivism in the post-intervention interval of approximately 12 months) for individuals in the treatment group were more than one and a half times as great as those for individuals in the control group. In relation to the mean recidivism rate for the control groups of about .40, this odds ratio indicates a recidivism reduction of 25% to a mean of .30. There was also significant variation across studies in the odds ratio for intervention effects (Q=214.02, df=57, p<.001). We turn now to an examination of the study characteristics associated with that variation.
How strong is the evidence?
The systematic review considered 58 studies meeting the criteria for systematic review out of a total of 1070 ‘promising’ studies (Lipsey et al., 2007: 9). The findings of the review confirmed the findings of previous systematic reviews of studies of CBT as a treatment for offending (Landenberger and Lipsey, 2005; Lipsey & Landenberger, 2006; Wilson et al., 2005; Pearson et al., 2002; Lipsey et al., 2001). The overall conclusion was that CBT is an effective approach to rehabilitation and reduces the risk of reoffending for many participants.
Is it worth it?
The review by Lipsey et al. (2007) did not consider the costing of these programmes, and there is limited available information on costs. Trained staff deliver CBT based Offender Behaviour Programmes, often over sustained periods, so it is reasonable to assume that it requires significant financial investment. Nonetheless, compelling evidence suggests that they can be cost- effective in terms of the overall objectives of the criminal justice system. Lipsey and colleagues found positive correlations between the length and number of sessions and the effectiveness of the intervention. Rather than being punitive, this approach is rehabilitative, thereby potentially saving money with every offender who does not reoffend. A Home Office study conducted with some 2000 offenders over a period of two years and using standard Home Office methodology estimated that for the treatment group of 667 offenders, there had been a reduction of 21, 000 crimes (Friendship et al., 2002).
Can it be implemented?
The review did not consider whether or not CBT could be implemented, but the breadth and scope of existing programmes suggests that this is not a significant issue. The review did find that the most effective programmes were characterised by the high quality of the implementation of the treatment, as evidenced by those programmes that had low drop-out rates, quality assurance processes and effective staff training (Lipsey et al., 2007). Whilst quality was important, the exact nature of the programme, for instance where it was implemented and by whom, and whether or not it was one of the ‘branded’ CBT programmes, was not found to significantly influence the success or otherwise of the programme.
What's missing from the evidence?
Despite a substantial body of research, there is relatively little evidence on which approaches within the broad umbrella of CBT are the most effective. The review by Lipsey and colleagues did consider this and found that there were some moderator variables, as described above. However, more research is needed to better understand what works best within an approach that is generally very effective. There is also limited evidence of the effectiveness of CBT programmes, or aspects of these programmes, in preventing offending amongst those identified as at risk of offending.