Two-Year Follow-Up on Return to Work in a Randomised Controlled Trial Comparing Brief and Multidisciplinary Intervention in Employees on Sick Leave Due to Low Back Pain

Purpose To study return to work (RTW) at 2-year follow-up in a randomised controlled trial comparing brief intervention (BI) and multidisciplinary intervention (MDI) in employees on sick leave due to low back pain (LBP) stratified for job relations. Methods In total 476 employees on sick leave for 4–12 weeks due to LBP were divided into strata with weak or strong job relations, based on perceived risk of losing job and influence on job planning. In each stratum participants were allocated to BI or MDI. All participants received BI, i.e. a clinical examination by a rheumatologist and physiotherapist. In addition, MDI involved a case manager who made a rehabilitation plan in collaboration with the participant. The primary outcome was time to RTW. Secondary outcomes were median weeks in different employment status and selfreported pain, disability and psychological health. Sustained RTW was estimated by work status the last 4 weeks before the 2-year date. Results Participants with strong job relations who received BI had a higher RTW rate (hazard ratio = 0.74 (95% CI 0.57; 0.96)) and spent more weeks working than participants who received MDI. In the stratum of weak job relations, no difference was seen regarding RTW and weeks working. For health-related outcomes and sustained RTW no significant results were found in neither stratum. Conclusions Employees with strong job relations achieved higher RTW rates when receiving BI compared to MDI, while no difference was found between intervention groups for employees with weak job relations. Trial Registration Current Controlled Trials ISRCTN14136384. Registered 4 August.