Cost-Effectiveness of guideline-based stepped and collaborative care versus treatment as usual for patients with depression – a cluster-randomized trial
Abstract Objective Depression is associated with major patient burden. Its treatment requires complex and collaborative approaches. A stepped-care model based on the German National Clinical Practice Guideline “Unipolar Depression” has been shown to be effective. In this study we assess the cost-effectiveness of this guideline based stepped care model versus standard care in depression. Methods This prospective cluster-randomized controlled trial included 737 depressive adult patients. Primary care practices were randomized to an intervention (IG) or a control group (CG). The intervention consisted of a four-level stepped care model. The CG received treatment as usual. A cost-utility analysis from the societal perspective with a time horizon of 12 months was performed. We used quality-adjusted life years (QALY) based on the EQ-5D as effect measure. Resource utilization was assessed by patient questionnaires. We calculated adjusted group differences in costs and effects, incremental cost-effectiveness ratios and cost-effectiveness acceptability curves. The complete sample and subgroups based on depression severity were considered. Results In the IG, adjusted mean total costs (+5,016; SE: €2,691) and effects (+0.008 QALY; SE: 0.02) were higher than in the CG; yet, differences were not statistically significant. Significantly increased costs were found in the IG for outpatient physician services and psychiatrist services. Significantly increased total and indirect costs in the IG were found in the group with severe depression. Incremental cost-effectiveness ratios were unfavourable and the probability of cost-effectiveness was low, except for the group with moderate depression (70% for willingness-to-pay threshold of €50,000/QALY). Conclusions We found no evidence for cost-effectiveness of the intervention. However, we identified indicators that the intervention works according to the aims of the National Treatment Guideline.