Quick Returns, Sleep, Sleepiness and Stress – A Field Study Investigating the Intra-Individual Effects on Objective Sleep and Diary Data

Introduction: Previous studies have associated quick returns (less than 11 hours of rest between shifts) with shortened sleep duration and increased sleepiness but have failed to find an association with sleep quality or stress. However, most previous work has relied on subjective measures of sleep which are limited. Thus, despite previous null results, an association with sleep quality cannot be ruled out. The aim of the present study is to examine how objective and subjective measures of sleep duration, sleep quality, sleepiness and stress are affected by quick returns compared with day- day transitions, in a sample of nurses and assistant nurses. The results have been published in the Scandinavian Journal of Work Environment and Health.

Methods: 225 nurses and assistant nurses wore actigraphy wristbands and kept a sleep and work diary for seven consecutive days. Sleep length was measured with actigraphy data. Sleep quality was assessed with both actigraphy data (sleep fragmentation index) and complementary subjective ratings (Karolinska sleep quality index, 1= poor, 5 = good). Participants also rated their stress and sleepiness (Karolinska sleepiness scale) levels every third hour throughout the workday and during leisure time (07AM-22PM). Quick returns and control conditions (day-day transitions) were identified from the reported working hours. As intra- individual differences were of interest, the data were analyzed in a linear mixed model where all participants acted as their own control. Thus, the final sample (N = 90) included those with at least one observation of both a quick return and a day-day transition.

Results: Quick returns were associated with shortened sleep length (-1 hour, 95% CI [-1.23, -0.81]), and a reduction in subjective sleep quality (-0.49, 95% CI [-0.69, -0.31]) compared with day-day transitions. The participants also experienced increased anxiety at bedtime (-0.38, 95% CI [-0.69, -0.08]) and increased worktime sleepiness during quick returns (0.45, 95%CI [0.22, 0.71]). No difference in sleep fragmentation and stress ratings was found.

Conclusion: Quick returns result in shortened sleep length, reduced subjective sleep quality and increased sleepiness during work, but do not seem to have an impact on perceived stress levels or sleep fragmentation among nurses and assistant nurses. Thus, managers, scheduling staff and employees should be cautious and consider the risk of fatigue when scheduling quick returns. Support: FORTE - Swedish Research Council for Health, Working Life and Welfare.

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Artikel online veröffentlicht:
08. Oktober 2025