Impact of biomechanical exposure (job-exposure matrix 'MADE') and social support on return to work following occupational injuries.

Objectives: To identify the determinants that influence the outcome of the return to work (RTW) after occupational injuries.

Methods: We conducted a cross-sectional study at the National Health Insurance Fund of Tunisia among victims of occupational injuries. Individual and professional factors have been evaluated through a face-to-face questionnaire for ten months. Biomechanical exposure was estimated by the job-exposure matrix "MADE" and social support by the Social Support Scale. Along with descriptive statistics, we used bivariate analysis, binary logistic regression, and random forest.

Results: We included 199 injured workers aged 20-60 years (mean = 42.73; 79.9 % male).Of the 199 injured workers, 39.7 % had unsuccessful RTW. Low social support, biomechanical exposure, blue-collar workers, working long hours, and severe injuries were associated with an unsuccessful return to work. In the variable importance plot issued from the random forest model, low social support at work was the most important risk factor of an unsuccessful RTW, followed by MADE variables: repetitiveness and effort.

Conclusion: Biomechanical exposure and social support are main influencers of the return-to-work process.