Roles of age, length of service and job in work-related injury: a prospective study of 63,620 person-years in railway female workers

The mechanisms through which age, length of service and job impact various work-related injury types remain unknown, especially among female workers. This prospective study evaluated their roles in injury among women. The population included all 22,952 permanently employed women at the French national railway company during 1998-2000 (63,620 person-years). In this follow-up period, 756 injuries with working days lost occurred (coded using the company’s injury classification, derived from that of the French health insurance scheme). We investigated the incidence of four injury types: fall on same level; fall to lower level; handling materials, equipment and objects; and other injuries. Data were analysed using negative binomial regression. Workers aged <25 had a higher risk for all injury types. Older workers (45-55 years) had a higher injury risk for falls on same and to lower level. For these falls the relative risk decreased steadily with increasing length of service in the company, from about 1.60 for one year to 0.50-0.60 for 30 years. For injuries from handling materials, equipment and objects the relative risk decreased from 1.05 for one year to 0.49 for 5-9 years, and then increased to about 1.50 for >20 years. In conclusion, younger age and shorter length of service are at risk for various injury types. Higher length of service is at risk for injury from handling materials, equipment and objects. Preventive measures should improve working conditions, provide knowledge through training, and help workers to be aware of risks associated with age, years of employment and job.