Inpatient or Outpatient Occupational Rehabilitation - What Works Best for Whom? A Non-randomized Clinical Trial

This study compared return-to-work (RTW) outcomes among Norwegian patients with musculoskeletal or common mental disorders participating in a 4-week inpatient or 3-month outpatient occupational rehabilitation program, examining associations between program type, pre-intervention sick-leave duration, and RTW.

An observational cohort (n = 857) was categorized into five pre-intervention benefit groups, including Group 1 (partial benefits for ≥ 6 weeks) and Group 2 (90-100% benefits for 6 weeks through 5 months). Primary outcome was time to stable RTW (first month without sickness benefits); secondary outcome was cumulative work participation over 24 months.

RTW hazard varied by group and time. During the first 3 months, outpatients in Group 1 had a threefold higher hazard of stable RTW than inpatients (HR = 3.61, p = .03). Between 3 and 10 months, the pattern reversed, favoring inpatients (outpatient HR = 0.68, p = .01). After 10 months, outpatients again had higher RTW hazards, significant only in Group 1. In Group 2, no outpatients achieved RTW during the first 3 months; furthermore, between 3 and 10 months, inpatients had a significantly higher RTW hazard (outpatient HR = 0.38, p = .02). Median months worked over 24 months was 18.1 for outpatients vs. 12.8 for inpatients in Group 1 (p = .08), and 0.6 vs. 5.3 in Group 2 (p = .04).

Pre-intervention sick-leave duration strongly influences RTW. Program effectiveness is time- and subgroup dependent. Patients with remaining work attachment (partial benefits) may benefit more from outpatient care, while those on full-time benefits for moderate durations benefit more from intensive inpatient programs, suggesting a need for stratified allocation.

Current controlled trials https://doi.org/10.1186/ISRCTN12033424 , 15.10.2014, retrospectively registered.