The Effects of Fatigue on Cognitive Performance in Police Officers and Staff During a Forward Rotating Shift Pattern

Background: Few studies have examined the effects of a forward rotating shift pattern on police employee performance and well-being. This study sought to compare sleep duration, cognitive performance and vigilance at the start and end of each shift within a three-shift, forward rotating shift pattern, common in United Kingdom police forces.

Methods: Twenty-three police employee participants were recruited from North Yorkshire Police (mean age 43). The participants were all working the same, 10-day, forward rotating shift pattern. No other exclusion criteria were stipulated. Sleep data were gathered utilising both actigraphy and self-reported methods; cognitive performance and vigilance was assessed using a customised test battery comprising of five tests; MPT, VOLT, NBACK, DSST and PVT. Statistical comparisons were conducted, taking into account Shift Type, Shift Number and the Start and End of each shift worked.

Results: Sleep duration was found to be significantly reduced following night shifts. Results showed a significant main effect of Shift Type in the VOLT and NBACK tasks and also a significant main effect of Start/End in the DSST task, along with a number of significant interactions.

Conclusion: The results of the tests indicated that learning and practice effects may have an effect on results of some of the tests. However, it is also possible that due to the fast rotating nature of the shift pattern, participants did not adjust to any particular shift, hence their performance in the cognitive and vigilance tests did not suffer significantly as a result of this particular shift pattern.