Abstract
BACKGROUND: Mental health comorbidities are common in physical long-term health conditions. AIMS: We evaluate the effectiveness of COMPASS, a therapist-supported, digital cognitive-behavioural therapy programme specifically designed to treat anxiety/depression in the context of long-term conditions. We also investigate patient experiences of the programme. METHOD: We utilised a mixed-methods, non-randomised design. We analysed pre-post data from 76 patients with long-term conditions who were receiving psychological treatment (COMPASS) via local NHS services, using paired sample t-tests and Cohen's d, with depression, anxiety, distress and functional impairment self-report scales. Qualitative interviews explored patients' experiences of using COMPASS. Twenty-one semi-structured interviews were completed and underwent inductive thematic analysis. RESULTS: Patients who received COMPASS had significantly reduced depression (-2.47, 95% CI -3.7 to -1.3, P < 0.001; Cohen's d = -0.376), anxiety (-2.30, 95% CI -3.6 to -1.2, P < 0.001; Cohen's d = -0.420) and psychological distress (-4.87, 95% CI -7.0 to -2.7, P < 0.001; Cohen's d = -0.422) and significantly improved functional impairment (-3.00, 95% CI -4.8 to -1.2, P ≤ 0.001; Cohen's d = -0.282). Effect sizes were larger when analyses included only patients with clinically significant baseline symptoms: depression (-4.02, 95% CI -5.6 to -2.5, P < 0.001; Cohen's d = -0.701), anxiety (-3.60, 95% CI -5.3 to -1.9, P < 0.001; Cohen's d = -0.739), psychological distress (-5.58, 95% CI -7.9 to -3.2, P < 0.001; Cohen's d = -0.523), functional impairment (-3.28, 95% CI -5.4 to -1.1, P ≤ 0.001; Cohen's d = -0.355). Qualitative analysis yielded two meta-themes: engagement and integration of mental and physical health. CONCLUSIONS: Results suggest that COMPASS is effective in NHS settings, and is acceptable to patients. Content tailored to long-term conditions, therapist support and clear delivery strategies should be prioritised to aid intervention implementation.