Abstract
The therapeutic community approach to psychological intervention has a long history of application in the context of offender rehabilitation. Its emphasis on the role of social interactions and interpersonal functioning in the encouragement and facilitation of change is one of this intervention's defining characteristics. However, the extent to which it actually effects change in offenders' interpersonal behaviour is still not fully understood. Interpersonal theory and the behavioural model that it proposes, the interpersonal circle, are founded on similar ideas to the therapeutic community concept, yet their relevance to the study of this intervention remains underexplored. The research described in this thesis has endeavoured to address this oversight. This work involved the longitudinal assessment of prisoners participating in a therapeutic community, principally using an observer-rated operationalisation of the interpersonal circle, the Chart of Interpersonal Relations in Closed Living Environments (CIRCLE). As the CIRCLE was employed in a novel setting and abbreviated form, the first stage in this research comprised an examination of its suitability to this application. Through a series of latent structural analyses, it was determined that the measure effectively operationalised the model upon which it was based. The next stage in this research involved an examination of how this interpersonal circle measure related to other assessment tools previously used in this setting. This study established that the CIRCLE was linked in a theoretically-consistent way with a number of these assessments, but also demonstrated that this measure provided an arguably more valid perspective compared to the primary assessment of interpersonal functioning previously used in this context. The final question addressed in this thesis concerned the interpersonal profile of the therapeutic community residents and how this changed in response to their participation in the intervention. This work established that such changes in interpersonal functioning were contingent on prisoners' completion of 18 months of therapy. The relevance of these changes to therapy engagement and subsequent recidivism were also examined. Ultimately, this work has established the applicability of interpersonal theory and its corresponding model of functioning to the study of prison-based therapeutic communities, and the utility of the insights that it can provide into both the process and outcome of this intervention approach.