Early interventions for primary care patients with stress-related mental ill health: a randomised controlled non-inferiority trial of a nurse-led collaborative care intervention versus cognitive behavioural therapy

Abstract

Background Stress-related mental ill health is highly prevalent, and most individuals first seek help in primary care where access to psychological support is often limited. Objective To test whether nurse-led collaborative care (CC) is non-inferior to cognitive behavioural therapy delivered as psychologist-guided self-help (GSH-CBT) in reducing stress for adult primary care patients with stress-related mental ill health. Methods A randomised controlled non-inferiority trial where 172 adult primary care patients with mild to moderate stress-related mental ill health were allocated to nurse-led CC or GSH-CBT (1:1). The primary outcome was the Perceived Stress Scale-10 administered every 3 weeks during the 12-week treatment phase. The a priori non-inferiority margin was 0.3 d , requiring the one-sided 95% CI of the effect size to fall within this bound. Secondary outcomes were symptoms of exhaustion, sleep problems, depressive symptoms, general anxiety and quality of life. Findings In both conditions, participants showed large, significant within-group improvements on the primary outcome and all secondary outcomes. The primary outcome showed a small between-group difference ( d =0.22), favouring GSH-CBT, with the CI upper bound (0.52) exceeding the non-inferiority margin. For secondary outcomes, GSH-CBT led to a greater reduction in exhaustion ( d =0.28; 95% CI 0.64 to 0.002). No other between-group differences were observed. Conclusions Nurse-led CC was not non-inferior to GSH-CBT. Effect differences were small, but improvements were slightly larger in GSH-CBT. Clinical implications Given that nurse-led CC is safe, easy to administer, and that significant within-group improvements were observed across all measures, this intervention could be a viable option in primary care settings where psychologist-delivered treatment is limited.