Is an expert diagnosis enough for assessment of sick leave for employees with musculoskeletal and mental disorders?

Purpose. The aim of this study is to determine differences in self-reported work ability, work conditions, health and function between ICD-10 groups with musculoskeletal disorders (MSD), mental disorders (MDs) and MSD + MD and to determine which variables are associated with sick leave. Method. A cross-sectional study of 210 employees was conducted at an occupational health service unit. Physiotherapists and physicians classified the employees' health problems according to ICD-10 and the employees answered a questionnaire with questions on demographic variables, health, functioning, work ability and work conditions. Results. Forty-four per cent of the employees had MSD, 22% had MD and 34% had a MSD + MD. The group on sick leave had worse results for all health and work measures. Belonging to the MD group, belonging to the MSD + MD group, having poor work ability and functioning were associated with being on sick leave. The value for the model explaining being on sick leave was 0.63 (Nagelkerke R-2). Conclusions. Having a diagnosis of MD based on a professional opinion and having poor work ability and functioning based on self-reports are associated with being on sick leave. The results suggest that self-reported data could be used to complement the expert-based diagnosis.