A follow-up study of workers with soft tissue injuries using the databases of the Ontario workplace safety and insurance board (WSIB)

grantor: University of TorontoA simple random sample of 5346 workers with lost-time claims of soft tissue injuries (STIs) in 1990 was generated and followed-up for a minimum of six years using the databases of the Ontario WSIB. An operational definition of recurrent lost-time claims was developed. Baseline exposures (sociodemographic, injury, health service received and workplace measures) and longterm outcomes (chance of recurrence, number of recurrences, total time on compensation and total costs) were obtained. Prognostic models for the relationships of exposures and outcomes were explored. Using seven days as a duration criterion for episode and gap between episodes, 19.4% of the study sample had at least one recurrent lost-time claim period during the follow-up and the number of recurrences ranged from 1 to 27. Total time on compensation and total costs were positively skewed, with means of 104.5 calendar days and 13,993.0 $Cdn. respectively and medians of 19 calendar days and 1085.7 $Cdn. respectively. Injury factors and types of health service received were the major predictors of the study outcomes. Injuries of back and upper limbs; specific diagnosis, inflammation, sprains/strains; overexertion as a cause of injury; and injuries requiring complex treatment or workers with a delayed health care billing were repeatedly associated with unfavorable outcomes. One or more poor outcomes were also predicted by some sociodemographic and workplace factors, including increased age; female worker; higher pre-accident wages; accident location around Toronto, county unemployment rate higher than 9.5%; smaller company; construction industry; and jobs requiring limb coordination and heavy physical work. To prevent prolonged work disability after work-related STIs, management should focus on the subgroups of workers who have a tendency to develop chronic injury. Further studies are necessary to clarify the significant relationships between exposures and outcomes, and provide evidence for management. The routinely collected administrative databases of the Ontario WSIB provide a broad picture of work disability in Ontario and contain basic information for epidemiologic studies. However, conduct of an epidemiologic study using the databases and interpretation of the study findings should consider the representativeness and limitations of the databases.Ph.D