Shift work and sickness absence at a Norwegian hospital: a longitudinal multilevel study

Shift work is known to be related to several negative health consequences and sickness absence. Research results regarding the relationship between types of shift schedules and sickness absence and whether and how individual factors moderate this relationship, are mixed though. The present paper aims to provide more insight in these relationships.

We used registry data from a large Norwegian hospital gathered for the years 2012-2016, for >14 000 employees. With random effects at the individual and unit levels, we analysed the relationship between shift schedule worked and sickness absence in the same year.

The results showed increased risk of short-term sickness absence for two-shift and three-shift rotations, as well as fixed night shifts compared with fixed-day shifts. We also found an increased number of absence periods for two-shift rotations without nights and three-shift rotations. Results for long-term sickness absence were mixed, with increased odds for two-shift rotations without nights, but reduced odds for three-shift rotations. We found partial support for a moderating influence of age, gender and parental status.

There is a clear relationship between working shifts and increased risk of short-term sickness absence. The relationship persists across gender, age group and parental status. The relationship between shift work and long-term sickness absence appears to be schedule and population specific. These findings may have implications for HR policies and the organisation of shift work in healthcare organisations.