Cameron A. Mustard, Andrea Chambers, Selahadin Ibrahim, Jacob Etches and Peter Smith, Institute for Work & Health, Toronto

Work-related musculoskeletal disorders (MSDs) are the leading cause of work disability in the developed economies. The objective of this study was to describe trends in the incidence of MSDs attributed to work exposures in Ontario over the period 2004-2011. It used an observational study of work-related morbidity obtained from three independent sources for a complete population of approximately six million occupationally active adults aged 15-64 in the largest Canadian province. The researchers implemented a conceptually concordant case definition for work-related, non-traumatic MSDs in three population-based data sources: emergency-department encounter record; lost-time workers’ compensation claims; and representative samples of Ontario workers participating in consecutive waves of a national health interview survey. Over the eight-year observation period, the annual per cent change (APC) in the incidence of work-related MSDs was −3.4 per cent (95 per cent CI −4.9 per cent to −1.9 per cent) in emergency departments’ administrative records, −7.2 per cent (−8.5 per cent to −5.8 per cent) in lost-time workers’ compensation claims and −5.3 per cent (−7.2 per cent to −3.5 per cent) among participants in the national health interview survey. Corresponding APC measures for all other work-related conditions were −5.4 per cent (−6.6 per cent to −4.2 per cent), −6.0 per cent (−6.7 per cent to −5.3 per cent) and −5.3 per cent (−7.8 per cent to −2.8 per cent), respectively. Incidence rate declines were substantial in the economic recession following the 2008 global financial crisis. The three independent population-based data sources used in this study documented an important reduction in the incidence of work-related morbidity attributed to non-traumatic MSDs. The results of this study are consistent with an interpretation that the burden of non-traumatic MSDs arising from work exposures is declining among working-age adults.

Occ Environ Med, Volume 72, Issue 4, pages 252-257. Correspondence to: Dr. Cameron Mustard, Institute for Work & Health, 481 University Avenue, Suite 800, Toronto, Ontario M5G 2E9; email: cmustard@iwh.on.ca.