Shift work and the incidence of injury among police officers.

BACKGROUND

Police officers may be injury prone due to fatigue, erratic work hours, and insufficient sleep. This study explored injury incidence among police officers across shifts.

METHODS

Day-to-day shift data from computerized payroll records (1994-2010) were available from a mid-sized urban police department (n = 430). Sleep duration, shift activity level, returning to work after days off, and injury incidence over time were also examined.

RESULTS

Age-adjusted incidence rate ratio (IRR) for injury on the midnight shift was 72% larger than the day shift (IRR = 1.72; 95% CI = 1.26-2.36) and 66% larger than the afternoon shift (IRR = 1.66; 95% CI = 1.23-2.25). Injury incidence for the first day back on the midnight shift was 69% larger than day shift (IRR = 1.69; 95% CI = 1.23-2.32) and 54% larger than the afternoon shift (IRR = 1.54; 95% CI = 1.36-1.76). High activity level combined with midnight shift work put officers at increased injury risk (IRR = 2.31; P = 0.0003). Probability of remaining free of injury was significantly higher for day shift than midnight shift (P < 0.0001).

CONCLUSIONS

Higher injury risk was associated with night shift work in police officers. Night shift combined with high work activity was strongly associated with injury risk. There was a significantly higher probability of not being injured on day compared to midnight or afternoon shifts.