Suffering of Common Mental Disorders but Still at Work: A Longitudinal Study During Periods of Differences in Regulations for Having Sick Leave.

The study observed naturally occurring work environments, so it cannot show that flexible hours or active jobs caused lower sick leave. The long study period covered many changes in diagnoses, work conditions, and insurance rules, which may make comparisons across periods unstable. Prescription information was available only from 2005, so fewer participants could be identified by antidepressant treatment in the earliest years. The sample was small in some strata, so the authors could not analyse subgroups such as people included by diagnosis versus medication. Participants were already working, so results may not apply to people with common mental disorders who are not working. Work environment exposures were self-reported, and only hospital diagnoses or prescribed antidepressants were used to identify common mental disorders. The authors tested thirteen different work factors, and they state that some findings could have arisen by chance.

Do not conclude that flexible working hours or active jobs caused less sick leave. This was a longitudinal observational study, and the authors tested thirteen different work factors, so chance findings and confounding remain possible.