Transient risk factors for slips, trips, and falls: A case-crossover study of US health care workers

Objectives: We conducted a case-crossover study to evaluate potential transient risk factors for a slip, trip or fall (STF) event among health care workers working in US hospitals.

Methods: Workers with a STF event (with or without an injury) reported to one of seven occupational health departments over a three-year period were interviewed via telephone. Workers provided responses to exposure questions for potential transient risk factors at the time of their STF event (hazard period), and for their past work week or month (control period). These factors include workplace-related (contamination, unusual pathway), work-task related (pushing/pulling, carrying), and worker-related (rushing, distraction). Short-term relative risks (incidence-rate ratios) were calculated using usual frequency analyses comparing exposure reported at the time of injury with average exposure estimated from the previous work month.

Results: A total of 153 workers were interviewed (131 women, 22 men), with a mean age (SD) of 46.1 years (20-67). Forty-nine percent slipped and fell, 28.8% tripped and fell. Preliminary findings suggest that the short-term relative risk (95% CI) of a STF was highest when walking on an unusual pathway, 86.8 (46.6-161.6) and when contamination was present, 39.8 (31.5-50.2). Other transient factors in decreasing order of short-term relative risk were carrying objects, being distracted, and being rushed. Pushing/pulling reduced the short-term STF relative risk by about 77%, RR=0.23 (0.12-0.45).

Conclusion: The results suggest the importance of transient, potentially modifiable factors in the etiology of STF events at work. The self-matched feature of the case-crossover study design controlled for stable between-person confounders