Effect of unionisation on workers’ compensation lost-time injury claim incidence, 2012–2018, by company size
| Average annual FTEs | No of businesses | Crude risk ratio (95% CI) | Adjusted risk ratio (95% CI) | |
| Unionised | Non-unionised | |||
| ≤4 | 1921 | 46 265 | 0.91 (0.78 to 1.06) | 0.98 (0.84 to 1.15) |
| 5–19 | 1628 | 7112 | 0.75 (0.68 to 0.83) | 0.75 (0.69 to 0.83) |
| 20–49 | 816 | 1276 | 0.79 (0.70 to 0.89) | 0.76 (0.67 to 0.86) |
| 50+ | 863 | 456 | 0.64 (0.55 to 0.74) | 0.56 (0.48 to 0.66) |
Regression analyses were conducted separately for each outcome, as described in the Methods section. Risk ratio is the risk of injury claims in unionised businesses divided by the risk in non-unionised. All risk ratios were derived from analyses with unionisation as the main independent variable. Adjusted risk ratios were from analyses including in addition company complexity, type of business activity and geographical region as covariates. Statistically significant risk ratios are shown in boldface. More detailed results can be found in Appendix G in Robson et al.24
FTE, full-time equivalent employees.