Cost-Effectiveness of a Health Promotion Intervention “Feel Good with Culture and Nature” for Adults with Mental Health Problems in Primary Care

Sammanfattning

Background: Common mental health problems place a substantial burden on healthcare systems, reduce productivity, and generate significant societal costs in Sweden. Nature- and culture-based interventions have shown promising effects in improving mental health outcomes, but robust economic evaluations of their cost-effectiveness are lacking. Aim: To conduct a cost-utility analysis (CUA) of the "Feel Good with Culture and Nature" (FGwNC) intervention in Region Uppsala, evaluating changes in health-related quality of life (HRQoL), societal costs, and assessing cost-effectiveness from a societal perspective. Method: A cost-utility analysis was conducted using a before-after design with 25 participants referred from primary care. Health-related quality of life was measured using a Swedish translation of the Recovering Quality of Life questionnaire (ReQoL-10) with utility values derived from the UK tariff. Costs included healthcare, medication, and productivity losses from paid and unpaid work (2024 SEK). Missing data at follow-up (28% attrition across all outcome variables) were managed using multiple imputation (m = 30). Uncertainty was assessed through non-parametric bootstrapping, deterministic sensitivity analyses, and probabilistic scenario-based cohort projections. Results: ReQoL-10 total scores improved significantly (Δ = 3.15; p = 0.048; dz = 0.44), while utility values showed a clinically meaningful but non-significant increase (Δ = 0.086; p = 0.114; dz = 0.36). Mean total societal costs decreased by 12,397 SEK per participant (p = 0.592), driven by reductions in sick leave (−24,721 SEK; p = 0.040) and unpaid work costs (−10,071 SEK; p = 0.068). The intervention was dominant from a societal perspective, with a 68.6% probability of dominance and 77% probability of cost-effectiveness at a willingness-to-pay threshold of 500,000 SEK/QALY. From a healthcare perspective, the ICER was 1,332,060 SEK/QALY, underscoring that cost savings were driven by productivity gains. Conclusion: The intervention appears cost-effective from a societal perspective. A value-of-perfect-information analysis indicated that the societal value of resolving the remaining decision uncertainty exceeded the estimated cost of a definitive randomized controlled trial (RCT), supporting investment in such a trial with longer follow-up. Results must be interpreted with caution given the before-after study design.