Aims
The purpose of this study was to investigate the sleep quality of nurses working irregular shifts, including night shifts, and to determine whether sleep quality is associated with the need for recovery.

Design
Descriptive cross-sectional study.

Methods
This study was conducted with 405 nurses working irregular shifts at Maastricht University Medical Center in Maastricht, the Netherlands, from September 2019 to January 2020. Data were collected using an online questionnaire that included sociodemographic characteristics, health, lifestyle behaviors, the Sleep-Wake Experience List, sleep problems, sleep duration, and the Need for Recovery scale. Data analysis was performed using descriptive statistics, chi-square tests, t-tests, and multiple linear regressions.

Results
Nurses who worked irregular shifts, including night shifts, had significantly poorer sleep quality (M = 3.3) than those who did not work night shifts (M = 2.8). In reference to daily functioning, nurses who worked irregular shifts, including night shifts demonstrated more difficulties than the latter (p < .009). Sleep quality was significantly associated with the need for recovery and remained so after controlling for confounding variables (β =.556, p < .001).

Conclusion
Nurses who work irregular shifts have poor sleep quality, particularly if they work night shifts. Sleep quality is strongly associated with nurses’ need for recovery after work.

Impact
The study’s findings indicate that the sleep quality of nurses who work irregular shifts, including night shifts, is lower than nurses who did not work night shifts, which was shown to be associated with a high need for recovery. Given that a high need for recovery has been demonstrated to be a strong predictor of ill health, the findings suggest that enhancing sleep quality in nurses working night shifts may lead to a lower need for recovery, which may in turn lead to better health and less risk for burnout and sickness absence.