Objectives: This study investigates the associations between recommended outcome measures for clinical pain trials, as outlined by The Initiative on Methods, Measurements and Pain Assessment in Clinical Trials (IMMPACT), and work ability among individuals with non-specific musculoskeletal disorders. Specifically, it examines how general health, physical and mental health, pain intensity, functional limitations, depression, and sleep quality relate to work ability in people with musculoskeletal disorders undergoing multimodal rehabilitation.

Methods: In this cross-sectional study, 116 participants were recruited from eight rehabilitation teams and two specialist care centers in central Sweden. The Work Ability Index (WAI), Short Form Health Survey (SF-36), Multidimensional Pain Inventory - Swedish version (MPI-S), and Montgomery-Åsberg Depression Rating Scale - Self-report (MADRS-S) were utilized to measure relevant constructs. Pearson correlations were calculated, followed by multiple linear regression analyses to assess the impact of the independent variables on work ability.

Results: Significant positive correlations were found between work ability and general health (r=0.346; p=0.001) and physical health (r=0.533, p=<0.001), while negative correlations were found with pain intensity (r=-0.423; p=<0.001), limitations in daily life (r=-0.536; p=<0.001), depression (r=-0.500; p=<0.001), and sleep quality (r=-0.431; p=<0.001). Taken together, the multiple linear regression analysis showed that limitations in daily life and depression were significantly associated with work ability, explaining a combined variance of 46.1 %.

Conclusions: This study emphasizes the importance of addressing mental health and daily functioning limitations in rehabilitation programs to enhance work ability among participants with musculoskeletal disorders. Tailored interventions targeting these areas could improve rehabilitation outcomes and support workforce participation in this population. Approved by the regional ethical review board of Uppsala (Dnr 2010/116).