Cognitive-behavioural therapy for schizophrenia in a forensic mental health setting

The efficacy of cognitive-behavioural therapy (CBT) for schizophrenia in community and general psychiatric settings has been widely investigated and its practice recommended in primary and secondary care. In secure forensic mental health services the evidence is less established. The purpose of this paper is to evaluate the effectiveness of group CBT for schizophrenia in a high secure hospital.

In all, 27 male forensic patients completed a manualised CBT group and were compared on primary and secondary outcomes to patients receiving treatment as usual (TAU). Primary outcomes were positive and negative symptoms as measured by the Scale for the Assessment of Positive Symptoms (SAPS), Scale for the Assessment of Negative Symptoms (SANS) and the Psychotic Symptom Rating Scales (PSYRATS). A secondary outcome was interpersonal functioning as measured by the Inventory of Interpersonal Problems (IIP-64).

CBT participants showed improvement on negative symptoms; affective flattening, alogia, anhedonia and avolition; in comparison to participants in TAU. CBT participants also showed reductions in delusions and hallucinations on the SAPS but not the PSYRATS. TAU participants improved on positive symptoms as measured by the PSYRATS. CBT participants showed reductions in overall interpersonal problems, and most notably in being socially inhibited and self-sacrificing. No iatrogenic effects of treatment were found; improvements in depression anxiety and stress were reported by group completers, which contrasted to experiences of the TAU group.

Absence of random allocation to CBP or TAU groups retains the risk of recruitment bias. Findings are preliminary given the sample size. Multiple outcome assessments increase risk of a type I error.

CBT for schizophrenia can be effective with clients in secure forensic mental health settings. Improvements in negative symptoms and interpersonal functioning appear to be particular gains. Self-report measures might be subject to specific demand characteristics in such settings.

The evaluation includes a comparator group in a high secure setting, which is typically absent in reported evidence for this population (Blackburn, 2004). The study also investigated changes in interpersonal functioning, which has previously been noted as an important but absent outcome in CBT for psychosis (Haddock et al., 2009). Iatrogenic outcomes were also considered in the evaluation to ensure no adverse effects were experienced from treatment.