Employees who change to day jobs from shift work still face high injury risk

Trading in shift work for a nine-to-five job may mean a better quality of life for many workers, but it doesn’t necessarily mean a lower risk of work-related illness and injury, a recent study has found.
An employee's risk of work-related injury may even increase shortly after she changes her work schedule into days, according to the study by Imelda Wong at the Institute for Work & Health (IWH).

Evidence shows that people working evening, night or rotating shifts face a higher risk of work-related injury than those who work days. But Wong’s study now shows the ones facing the highest risks are those who change from day jobs into shift work, as well as those who change out of shift work into days. (Note that these refer to permanent or indefinite shift changes, not those linked to rotating shift work.)

“This is surprising because we expected that moving into a daytime job may improve sleep and create a better work-life balance, thereby reducing the risk of work-related injury,” said Wong. “But we found that people who switch from nights to days are still two-and-a-half times as likely to get injured as those who have always worked days.”

Wong’s analysis looked at four categories of workers: those who only work days; those changing from days to non-standard shifts; those changing from shifts to days; and those working non-standard shifts the entire time. (People whose shifts changed routinely, as part of rotating-shift arrangements, were treated as non-standard shift workers.)

Compared to day workers, long-term non-standard shift workers were 1.5 times more likely to be injured. However, the risks were even greater for those changing work schedules, whether to or from shift work. Those changing from day shifts into non-standard shifts were 2.6 times more likely to get hurt due to work; those changing into day shifts were 2.4 times more likely.

It’s still too early to say why the risk of sustaining work injury among shift workers remains high even after they change into daytime work. The data used in this study did not have any information that would help shed some light on that question.

“It’s an interesting and concerning finding. At this time we can only speculate on what may be contributing to an elevated risk for those who switch from nights to days,” says Wong. “Still, I think this study tells us we need health and safety policies and programs for people who have made a change in shift schedules. It’s important to pay attention to health and injury risks even after someone has stopped working nights and moved into days.”

Uyen Vu is the editor of At Work, IWH's newsletter. This article originally appeared in the Fall 2014 issue of At Work. The complete article can be viewed here.