Evaluating the Health and Economic Impacts of Return-to-Work Interventions: A Modeling Study

Objectives: The rate of sickness absence in Norway is at its highest point since 2009, and policymakers need tools to make informed decisions on high-value interventions to address sick leave. Using trial-linked registry data, multi-state modeling, and decision-analytic modeling, we assessed the cost-effectiveness of 2 return-to-work (RTW) interventions for individuals with musculoskeletal and psychological disorders in Norway. Methods: Using data from 166 individuals in a randomized trial, we developed a decision-analytic model to compare 2 multidomain RTW interventions: outpatient acceptance and commitment therapy (O-ACT) and inpatient multimodal occupational rehabilitation (I-MORE). The probabilistic model was informed using trial-based input parameters, including transition probabilities, healthcare costs, production loss, and health-related quality of life to project long-term costs and quality-adjusted life-years (QALYs) over a 25-year time horizon for each intervention. Results: Modeled outcomes were consistent with the trial outcomes, showing that I-MORE led participants to RTW more quickly. However, assuming a healthcare perspective and a cost-effectiveness threshold of $50 000 per QALY, I-MORE was not considered cost-effective in 98% of our simulations (probabilistic incremental cost-effectiveness ratio, $356 447 per QALY gained) compared with O-ACT. In contrast, when accounting for production loss, I-MORE not only became cost-effective but also was projected to be more beneficial and less costly than O-ACT. Conclusions: Under current Norwegian benchmarks for cost-effectiveness, I-MORE would not be considered cost-effective unless production loss was included. Our findings emphasize the key role of a broader societal perspective in economic evaluations, which, although it is being considered, is currently not recommended in Norwegian guidelines.