Geographic variation in work injuries: a multilevel analysis of individual-level data and area-level factors within Canada.

PURPOSE: This study sought to examine provincial variation in work injuries and to assess whether contextual factors are associated with geographic variation in work injuries. METHODS: Individual-level data from the 2003 and 2005 Canadian Community Health Survey was obtained for a representative sample of 89,541 Canadians aged 15 to 75 years old who reported working in the past 12 months. A multilevel regression model was conducted to identify geographic variation and contextual factors associated with the likelihood of reporting an activity limiting work injury [corrected], while adjusting for demographic and work variables. RESULTS: Provincial differences in work injuries were observed, even after controlling for other risk factors. Workers in western provinces such as Saskatchewan (adjusted odds ratio [AOR], 1.30; 95% confidence interval [CI], 1.09-1.55), Alberta (AOR, 1.31; 95% CI, 1.13-1.51), and British Columbia (AOR, 1.46; 95% CI, 1.26-1.71) had a higher risk of work injuries compared with Ontario workers. Indicators of area-level material and social deprivation were not associated with work injury risk. CONCLUSIONS: Provincial differences in work injuries suggest that broader factors acting as determinants of work injuries are operating across workplaces at a provincial level. Future research needs to identify the provincial determinants and whether similar large area-level factors are driving work injuries in other countries.

Validation of a risk factor-based intervention strategy model using data from the readiness for return to work cohort study.

BACKGROUND: Low back pain (LBP) is a common and in some cases disabling condition. Until recently, workers presenting with non-specific LBP have generally been regarded as a homogeneous population. If this population is not homogeneous, different interventions might be appropriate for different subgroups. We hypothesized that (1) Clusters of individuals could be identified based on risk factors, (2) These clusters would predict duration and recurrences 6 months post-injury. METHODS: The study focuses on the 442 LBP claimants in the Readiness for Return-to-Work Cohort Study. Claimants (n = 259) who had already returned to work, approximately 1 month post-injury were categorized as the low risk group. A latent class analysis was performed on 183 workers absent from work, categorized as the high risk group. Groups were classified based on: pain, disability, fear avoidance beliefs, physical demands, people-oriented culture and disability management practice at the workplace, and depressive symptoms. RESULTS: Three classes were identified; (1) workers with 'workplace issues', (2) workers with a 'no workplace issues, but back pain', and (3) workers having 'multiple issues' (the most negative values on every scale, notably depressive symptoms). Classes 2 and 3 had a similar rate of return to work, both worse than the rate of class 1. Return-to-work status and recurrences at 6 months were similar in all 3 groups. CONCLUSION: This study largely confirms that several subgroups could be identified based on previously defined risk factors as suggested by an earlier theoretical model by Shaw et al. (J Occup Rehab 16(4):591-605, 2006). Different groups of workers might be identified and might benefit from different interventions.

Changes in job stressors in the Canadian working population.

OBJECTIVES: To determine the changes in levels of work stressors in a nationally representative sample of Canadian workers from 1994/95 to 2000/01. METHODS: We compared responses for an abbreviated version of the Job Content Questionnaire in two waves of the National Population Health Survey (NPHS). Other items and scales related to work and health were also analyzed. Data were transformed to range from 0 to 10. Comparisons of the 2000/01 data were also made with the Canadian Community Health Survey (CCHS) conducted in 2000. RESULTS: There were only very small absolute differences between NPHS 2000/01 data and CCHS 2000 data. The NPHS comparison from 1994/95 to 2000/01 showed an increase in job security (change in means = 0.49, 95% CI 0.39 to 0.58) and a decrease in job physical demands (change in means = 0.45, 95% CI 0.35 to 0.54). Other changes in work characteristics were small in absolute value. The combined "overall work stressors" index dropped by 0.12 (95% CI 0.08 to 0.15). CONCLUSIONS: Levels of work stressors did not increase over the period. Some subscales showed an improvement.