A case-crossover study of work-related acute traumatic hand injuries in the People’s Republic of China

Abstract

The aim of this study was to quantify potential transient risk factors for occupational acute hand injury among hospitalized workers in the People's Republic of China (PRC). Participants were recruited from 11 medical facilities in 3 cities of the PRC. A face-to-face interview was used to collect information on the occurrence of 8 potential risk factors within a 90-minute time period before an acute traumatic hand injury and during a control period within the month before the injury. The reliability of reporting transient risk factors was assessed, and a case-crossover design was used to estimate the injury incidence risk ratio (IRR) of each risk factor. In total,703 hospitalized workers completed the interview (527 male, 176 female), with a mean age of 31.8 [standard deviation (SD) 10.3] years. The median time interval between injury and interview was four days. Thirty percent of participants had a crush injury and 25.7% had an amputation. Using malfunctioning machinery/tools/material, performing a task with a different method, working overtime, and wearing gloves were found to have good reliability in test-retest examination [intra-class correlation coefficient (ICC)>0.9]. The IRR of a hand injury were markedly increased while using malfunctioning machinery/tools/material [110.4, 95% confidence interval (95% CI) 97.4-125.2], performing a task with a different method than usual (84.3, 95% CI 67.7-105.1), or being distracted (69.6, 95% CI 57.9-83.7). Gender and size of company were associated with differences in glove usage. The results suggest the importance of transient, potentially modifiable factors in the etiology of occupational acute hand injury in the PRC. Regular maintenance of machinery/tools, work practice controls, and avoiding distractions should be priorities for reducing the risk of occupational acute hand injuries.