A case-crossover study of transient risk factors for occupational acute hand injury

Abstract

Background: Workers with acute hand injuries account for over 1 000 000 emergency department visits annually in the United States. Aims: To determine potential transient risk factors for occupational acute hand injury. Methods: Subjects were recruited from 23 occupational health clinics in five northeastern states in the USA. In a telephone interview, subjects were asked to report the occurrence of seven potential risk factors within a 90-minute time period before an acute hand injury. Each case also provided control information on exposures during the month before the injury. The self-matched feature of the study design controlled for stable between-person confounders. Results: A total of 1166 subjects were interviewed (891 men, 275 women), with a mean age (SD) of 37.2 years (11.4). The median time interval between injury and interview was 1.3 days. Sixty three per cent of subjects had a laceration. The relative risk of a hand injury was increased when working with equipment, tools, or work pieces not performing as expected (11.0, 95% CI 9.4 to 12.8), or when using a different work method to do a task (10.5, 95% CI 8.7 to 12.7). Other transient factors in decreasing order of relative risk were doing an unusual task, being distracted, and being rushed. Wearing gloves reduced the relative risk by 60% (0.4, 95% CI 0.3 to 0.5). Occupational category, job experience, and safety training were found to alter several of these effects. Conclusion:The results suggest the importance of these transient, potentially modifiable factors in the aetiology of acute hand injury at work. Attempts to modify these exposures by various strategies may reduce the incidence of acute hand injury at work.

Epidemiology and Sequelae of Workplace Hand Injuries at a Tertiary Trauma Care Centre

“…In Netherland and Denmark, hand injuries peak in the age group 10 -14 years, 44% in 10 -19 years in Canada, 35% (under 15 years) in Turkey [5]- [8]. 65% of the victims of industrial injuries in our study were literate (10 years in school and 3 years diploma) in comparison to 41% in the Turkish study [9]- [11]. In our study 91% were right hand dominant and 42.5% had only right hand injury, 40% had bilateral hand injury and 17.5% had left hand injury [12].…”

Transient risk factors of acute occupational injuries: a case-crossover study in two Danish emergency departments

“…Furthermore, results from previous studies highlight that equipment-related factors seem to have the highest OR followed by practice-related factors and subsequently worker-related factors. However, only one study (14) has highlighted these tendencies in risk estimates.…”

“…Most previous studies have focused on specific injuries, eg, hand or eye injuries (14,18,20,21) or specific industries, such as pork processing and commercial fishing (18,22). However, there is a need to compare the influence of transient risk factors across different kinds of occupational injuries and injury severity (23).…”

“…If recall diminishes over days or weeks, then an overestimation of some transient risk factors, as mentioned before, at the time of the injury coupled with underestimation in the control periods would result in artificially high risk estimates. Some studies reinterview subjects and indicate that this is not a problem for most transient risk factors (14,35).…”

“…A case-crossover design is well-suited to examine transient risk factors as the case is self-matched, ie, exposure in the interval immediately before an outcome (injury) occurs is compared to exposure during a previous time interval when the outcome did not occur (14). Accordingly, each individual serves as their own control, and confounders that remain constant over the compared periods (age, gender, specific job task, experience etc) are inherently adjusted for, in contrast to the standard case-control design (15,16).…”