Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article


Doctor of Philosophy


Health and Rehabilitation Sciences


Alvarez, L.

2nd Supervisor

Classen, S.


University of Florida

Joint Supervisor


Almost half of Canadian healthcare workers are employed in rotating day/night shifts to provide essential 24-hour services. However, poor sleep quantity and quality are pervasive in shiftwork and may negatively impact cognitive functions required for driving. Furthermore, healthcare shiftworkers (HCSW) are under-represented in research examining shiftworkers’ sleep and driving performance. Thus, this dissertation examined sleep, sleepiness and driving performance in HCSW via three aims. First, chapter 2 aimed to quantify and describe HCSWs’ sleep-related driving experiences and advance the understanding of occupational adaptations used by HCSWs to meet driving demands. Second, chapter 3 aimed to quantify differences in sleep, sleepiness, and driving performance outcomes between HCSW and dayworkers (DW). Finally, chapter 4 aimed to identify whether demographic, sleep- or driving-related outcomes may predict the 6-week sum of adverse driving events reported.

Chapter 2 findings show that the majority of HCSWs experienced insufficient sleep during their workweek and reported elevated rates of risky and sleep-related driving behaviours. Despite recurring, multi-layered adaptations to mitigate the risk of sleep-related driving events, 90% of HCSW reported at least sleep-related driving events in the past year, described as a routine and predictable consequence of shiftwork. Limited training, resources, and unpredictable scheduling were highlighted as systemic barriers disproportionately affecting younger HCSW. Chapter 3 findings show that HCSW (versus DW) experience significantly lower sleep quantity and quantity, and more frequent occurrences of severely insufficient sleep below thresholds indicated for impaired driving. Further, HCSW reported higher ratings of subjective sleepiness and higher occurrences of sleep-related and adverse driving events. Chapter 4 findings identified shiftwork, younger age, higher scores on the Pittsburg Sleep Quality Index, and more frequent occurrences of sleep <6h/24h as factors significantly predicted a higher 6-week sum of adverse driving events. Overall, findings suggest that HCSW are an at-risk group of drivers, with important implications in future research, healthcare worker education, and policy, with a crucial need to focus on younger workers.

Summary for Lay Audience

In Canada, almost half of healthcare employees work rotating day/night shifts to provide 24-hour care. However, shiftworkers commonly report short or low-quality sleep, which can impact mental abilities needed for driving. Unfortunately, healthcare shiftworkers (HCSW) have not been included in research on shiftwork and driving. Therefore, the goal of this dissertation is to examine HCSW sleep, sleepiness, and driving with three goals. Chapter 2 examines HCSWs’ self-reported sleep, sleep-related driving events (e.g., sleepiness), or negative driving events on-road (e.g., leaving lane), and describes HCSWs’ sleep-related driving experiences and coping strategies. Chapter 3 examines whether HCSW (versus day workers, DW) differed in sleep, sleepiness, and driving outcomes. Chapter 4 examines what factors (e.g., about the person, their sleep or driving outcomes) might identify how many negative driving outcomes they report over 6 weeks. Chapter 2 shows that 65% of HCSWs reported short sleep at least weekly and reported more often engaging in risky or sleepy driving behaviours. Despite using multiple strategies to reduce sleepy driving experiences, 90% reported severe sleepiness while driving in the past year, and suggested this was a regular, predictable result of shiftwork. Barriers primarily impacted younger workers, such as included little training or support and unpredictable schedules. Chapter 3 shows that HCSW had shorter and lower quality sleep overall, and more often had very short sleep below levels considered to cause impaired driving. Healthcare SW also reported a higher level of sleepiness while driving and a higher number and type of negative driving events than DW. Chapter 4 shows that factors including shiftwork, younger age, poorer quality sleep and more often having very short sleep predicted the highest number of negative driving events over a 6-week period. Overall, these findings show HCSW are an at-risk group of drivers due to poor sleep quantity, decreased sleep quantity, increased sleepiness, and higher number and type of negative driving events. These findings will inform healthcare worker education, workplace policy, and future research.

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Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.