Comparing current definitions of return to work: a measurement approach.

INTRODUCTION: Return-to-work (RTW) status is an often used outcome in work and health research. In low back pain, work is regarded as a normal activity a worker should return to in order to fully recover. Comparing outcomes across studies and even jurisdictions using different definitions of RTW can be challenging for readers in general and when performing a systematic review in particular. In this study, the measurement properties of previously defined RTW outcomes were examined with data from two studies from two countries. METHODS: Data on RTW in low back pain (LBP) from the Canadian Early Claimant Cohort (ECC); a workers' compensation based study, and the Dutch Amsterdam Sherbrooke Evaluation (ASE) study were analyzed. Correlations between outcomes, differences in predictive validity when using different outcomes and construct validity when comparing outcomes to a functional status outcome were analyzed. RESULTS: In the ECC all definitions were highly correlated and performed similarly in predictive validity. When compared to functional status, RTW definitions in the ECC study performed fair to good on all time points. In the ASE study all definitions were highly correlated and performed similarly in predictive validity. The RTW definitions, however, failed to compare or compared poorly with functional status. Only one definition compared fairly on one time point. CONCLUSIONS: Differently defined outcomes are highly correlated, give similar results in prediction, but seem to differ in construct validity when compared to functional status depending on societal context or possibly birth cohort. Comparison of studies using different RTW definitions appears valid as long as RTW status is not considered as a measure of functional status.

Prognostic factors for disability claim duration due to musculoskeletal symptoms among self-employed persons.

BACKGROUND: Employees and self-employed persons have, among others, different personal characteristics and different working conditions, which may influence the prognosis of sick leave and the duration of a disability claim. The purpose of the current study is to identify prognostic factors for the duration of a disability claim due to non-specific musculoskeletal disorders (MSD) among self-employed persons in the Netherlands. METHODS: The study population consisted of 276 self-employed persons, who all had a disability claim episode due to MSD with at least 75% work disability. The study was a cohort study with a follow-up period of 12 months. At baseline, participants filled in a questionnaire with possible individual, work-related and disease-related prognostic factors. RESULTS: The following prognostic factors significantly increased claim duration: age > 40 years (Hazard Ratio 0.54), no similar symptoms in the past (HR 0.46), having long-lasting symptoms of more than six months (HR 0.60), self-predicted return to work within more than one month or never (HR 0.24) and job dissatisfaction (HR 0.54). CONCLUSIONS: The prognostic factors we found indicate that for self-employed persons, the duration of a disability claim not only depends on the (history of) impairment of the insured, but also on age, self-predicted return to work and job satisfaction.

Participatory ergonomics as a return-to-work intervention: a future challenge?

BACKGROUND: Participatory ergonomics (PE) are often applied for prevention of low back pain (LBP). In this pilot-study, a PE-program is applied to the disability management of workers sick listed due to LBP. METHODS: The process, implementation, satisfaction, and barriers for implementation concerning the PE-program were analyzed quantitatively and qualitatively for 35 workers sick listed 2-6 weeks due to LBP and their ergonomists. RESULTS: Two-hundred-and-seventy ergonomic solutions were proposed to the employer. They were targeted more at work design and organization of work (58.9%) than at workplace and equipment design (38.9%). They were planned mostly on a short-term basis (74.8%). Almost half (48.9%) of the solutions for work adjustment were completely or partially implemented within 3 months after the first day of absenteeism. Most workers were satisfied about the PE-program (median score 7.8 on a 10-point scale) and reported a stimulating effect on return-to-work (66.7%). Main obstacles to implementation were technical or organizational difficulties (50.0%) and physical disabilities of the worker (44.8%). CONCLUSIONS: This study suggests that compliance, acceptance, and satisfaction related to the PE-program were good for all participants. Almost half of the proposed solutions were implemented.