Rumination-Focused Cognitive Behavioral Therapy for Negative Symptoms in Early Psychosis: Results of a Pilot Randomized Clinical Trial

INTRODUCTION: Repetitive negative thinking may contribute to negative symptoms in psychosis. We report clinical outcomes from a pilot randomized clinical trial evaluating the feasibility and efficacy of group rumination-focused cognitive behavioural therapy (RFCBT) added to early outpatient care (OPUS) versus OPUS alone, i.e., treatment-as-usual (TAU). METHODS: Young adults with schizophrenia spectrum disorders receiving OPUS care were randomized 1:1 to 13 weeks of group RFCBT plus OPUS or to TAU. Assessments were conducted at baseline and post-treatment. Feasibility was defined as ≥80% of participants completing ≥six sessions. The primary outcome was Brief Negative Symptom Scale (BNSS). Secondary outcomes were Perseverative Thinking Questionnaire (PTQ), Ruminative Responses Scale (RRS), Scale for the Assessment of Positive Symptoms (SAPS), Calgary Depression Scale for Schizophrenia (CDSS), Behavior Rating Inventory of Executive Function (BRIEF), and Social Functioning Scale (SFS). Between-group differences in change scores were tested with Welch t-tests. RESULTS: Fifty-nine participants were included, but one withdrew consent, meaning fifty-eight participants were analyzed intention-to-treat (RFCBT n=28, TAU n=30). The treatment was feasible with 82.14 % of participants in the RFCBT group completing ≥six sessions. Compared with TAU, RFCBT produced greater improvement in BNSS (between-group Δ -5.90; p=0.05; d=0.72). Repetitive negative thinking and rumination improved significantly: PTQ (Δ -8.35; p=0.016; d=0.89) and RRS (Δ -9.62; d=1.15; p=0.001). No significant between-group differences were observed for SAPS, CDSS, BRIEF, or SFS. CONCLUSION: Adding group RFCBT to OPUS was feasible and yielded large reductions in negative symptoms and repetitive negative thinking relative to TAU, supporting progression to a fully powered trial.