Objectives: The aim of the present study was to investigate whether the direction of shift rotation was related to the need for recovery, fatigue, sleep quality, work-family conflict, and leisure time among three-shift workers.
Methods: Data of 95 workers in forward-rotating three-shift work and 681 workers in backward-rotating three-shift work, with 32 months of follow-up, in the Maastricht cohort study (N=12,095) were used. Both cross-sectional and longitudinal analyses were carried out.
Results: A backward rotation schedule was prospectively related to an increased need for recovery [relative risk (RR) 2.88, 95% confidence interval (95% CI) 1.06-7.81] and poor general health (RR 3.21, 95% CI 1.32-7.83), as compared with a forward rotation schedule. Adjustment for demographic and health variables and the characteristics of the work environment did not alter these relations considerably. Furthermore, a forward rotation schedule was prospectively related to less work-family conflict and better sleep quality over the 32 months of follow-up. Finally, high levels of fatigue, need for recovery, poor sleep quality, poor general health, insufficient leisure time, and work-family conflict at first measurement were associated with an increased risk of leaving shiftwork during the follow-up.
Conclusions: Optimization of shiftwork schedules, in terms of shift rotation, seems a promising method for decreasing the negative impact accompanying shiftwork. Future studies should investigate whether these findings for three-shift workers are applicable to other shiftwork schedules as well. Furthermore, this study clearly illustrates the existence of secondary selection processes among shiftworkers and thereby emphasizes the complexity of valid shiftwork research.