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Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments
Published on: August 8, 2019
On-call work schedules, sleep knowledge, and sleep quality in medical trainees: results from a UK pilot study
Cheng Zhang1,2,3, John J R M Raj2, Karen Spruyt4
1Centre for Human & Applied Sciences (CHAPS), Faculty of Life Sciences & Medicine, King's College London, London, UK.
Background:
Evidence suggests that shift work and nocturnal on-call rotations have negative effects on the health of medical trainees. Data regarding the optimal frequency and duration of shifts that benefit the health of medical trainees, patient safety, and medical education are inconclusive. Additionally, the extent of medical trainees' knowledge about sleep medicine and its impact on their well-being during on-call periods remains unclear. The aim of this study was to evaluate the knowledge of trainees around sleep when on call and further elicit the impact of on-call periods on their sleep.
Methods:
We sought to gather data on the effect of shift work and being on-call on sleep in medical trainees. The study was prospectively registered on ClinicalTrials.gov (NCT06706453; registered 11/09/2024). It was designed as a cross-sectional, online survey conducted through a secure online link (REDCap 14.0.42, Vanderbilt University, Nashville, TN, USA) to cover (I) demographics and place of work; (II) basic knowledge and perception of sleep; (III) sleep routine during "on-call" and "off-call"; and (IV) sleep-related questionnaires [Epworth Sleepiness Scale (ESS) and Insomnia Severity Index (ISI)]. A level of significance was indicated at P<0.05. Medical trainees were recruited through online distribution of the survey link via professional networks, institutional mailing lists, and trainee groups.
Results:
The study was open between February and April 2025, with 107 respondents [mean ± standard deviation (SD): age 32±6 years; height 1.70±0.10 m; weight 69.3±14.6 kg; 41% male, 55% female, 4% identified as other; 28% were single, 73% lived in a relationship, and 32.0% had children; 82% were resident physicians]. The regular on-call working time per day was significantly higher than when not being on call, with a median of 13 [interquartile range (IQR), 12, 13] vs. 9 (IQR, 9, 10) hours, P<0.05. During on-call periods, respondents experienced shorter sleep duration with 6 (IQR, 5, 7) vs. 7 (IQR, 6.5, 8) hours, more difficulties falling asleep (70% vs. 27%) and maintaining sleep (63% vs. 23%), and required more daytime naps (50% vs. 12%) (P<0.05, respectively). Time on the commute (one way) was negatively correlated with self-rated current sleep (Spearman r=-0.492; P=0.01). Knowledge about obstructive sleep apnea (OSA) was positively correlated with the sense of well-being (Spearman r=0.426; P=0.03), negatively correlated with the ESS score (Spearman r=-0.429; P=0.046), and negatively correlated with early awakening (Spearman r=-0.378; P=0.043).
Conclusions:
Medical trainees in the UK experience long on-call working hours with an impact on sleep quality and quantity. These findings have implications on work performance and social interactions. Sleep education may be used to improve sleep and well-being.
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