Prediction of Outcome for Veterans with Post-Traumatic Stress Disorder Using Constructs from the Transtheoretical Model of Behaviour Change

Abstract

Objective: Post-traumatic stress disorder (PTSD) is a disabling condition, sometimes unresponsive to treatment. The aim of the present study was to examine the predictive utility of constructs from the transtheoretical model of behaviour change (TTM) known to predict outcome for other disorders. Method: A sample of 50 veterans presenting for a PTSD treatment programme provided data for this longitudinal study. Variables were assessed at four time-points during the treatment programme. Multiple regression and mixed-effects regression were utilized to determine the predictive utility of variables from the TTM. Results: Allocated stage of change at the time of a 2 day introduction programme predicted follow-up symptom severity, but changes therein during treatment did not predict changes in symptom severity. However, changes in the continuous readiness-to-change variable and behavioural processes of change were predictive of such changes. Conclusions: Despite some difficulties in the application of the TTM to PTSD, the model does appear to predict treatment outcome. Veterans who have increased readiness to change and who make more use of behavioural processes of change are likely to have improved outcomes.