Supplementary Material for: The Effectiveness of a Patient-Centred Assessment with a Solution-Focused Approach (DIALOG+) for Patients with Psychosis: A Pragmatic Cluster-Randomised Controlled Trial in Community Care

Background: DIALOG+ was developed as a computer-mediated intervention, consisting of a structured assessment of patients' concerns combined with a solution-focused approach to initiate change. This study tested the effectiveness of DIALOG+ in the community treatment of patients with psychosis. Method: This was a pragmatic, exploratory, parallel-group, cluster-randomised controlled trial. Clinicians within community teams - along with patients with psychosis under their care - were randomised to use DIALOG+ once per month for 6 months or an active control. The primary outcome (subjective quality of life, SQOL) and secondary outcomes were assessed after 3, 6 and 12 months by blinded assessors and analysed using mixed-effect models. Results: A total of 49 clinicians and 179 patients were randomised. Implementation of DIALOG+ was variable, with an average of 1.8 sessions (SD = 1.6) in the first 3 months and 1.1 (SD = 1.2) in the following 3 months. Patients in the DIALOG+ arm had better SQOL at 3, 6 and 12 months (p = 0.035, 0.058 and 0.014, respectively; Cohen's d = 0.29-0.34). They also had significantly fewer unmet needs at 3 and 6 months, fewer general psychopathological symptoms at all time points and better objective social outcomes at 12 months, with no significant differences in other outcomes. Overall care costs were lower in the intervention group. Conclusion: Despite variable implementation, DIALOG+ is a beneficial intervention for community patients with psychosis. As a non-expensive and potentially cost-saving, generic intervention, DIALOG+ may be widely used and may improve the effectiveness of community treatment. Further trials should test DIALOG+ in different patient groups and contexts.