Early school start time may compromise academic success of university students

University students in Singapore appear to be having trouble keeping up with early classes, being more likely to miss class, get fewer hours of sleep, and achieve a lower grade point average, as shown in a study.

Wi-Fi connection log data from 23,391 students showed that the attendance rate for lecture classes that started at 08:00 was significantly lower than that for lecture classes that started at 10:00 or later. The difference in attendance rate was 7.6 percent for 09:00 vs 08:00 classes (p=0.64), 11.1 percent for 10:00 vs 08:00 classes (p=0.032), 11.0 percent for 12:00 vs 08:00 classes (p=0.043), 10.8 percent for 14:00 vs 08:00 classes (p=0.047), and 11.3 percent for 16:00 vs 08:00 classes (p=0.032). [Nat Hum Behav 2023;doi:10.1038/s41562-023-01531-x]

When sleep behaviour was assessed in a subset of 181 students who underwent a 6-week actigraphy study during the school semester, students happened to sleep past the start of class and woke up too late to reach class on time on many occasions. Also, the students were more likely to nap on days when classes started early in the morning, with the frequency of napping significantly associated with class start time (p<0.001).

According to the investigators, they found evidence to suggest that early morning classes may contribute to a university-wide sleep debt and circadian misalignment.

“Students went to bed at around the same time but woke up earlier to attend morning classes. Consequently, nocturnal sleep duration was shorter only on nights that preceded morning classes,” they added.

Both total sleep time at night and time in bed for sleep decreased with earlier class start times, such that students were sleeping an hour shorter on days when classes started at 08:00 than on nonschool days.

Finally, having early morning classes on more days of the week correlated with poorer academic performance. Students without morning classes had a much higher grade point average than those with morning classes, regardless of their frequency. Having morning classes on 3–5 days of the week was associated with a medium effect size on grade point average (3 days: −0.37; 4 days: −0.42; 5 days: −0.40). The difference in grade point average relative to having no days with morning classes was −0.069 for 1 day per week (p<0.001), −0.103 for 2 days per week (p<0.001), −0.117 for 3 days per week (p<0.001), −0.141 for 4 days per week (p<0.001), and −0.146 for 5 days per week (p<0.001).

“[We] showed that sleep behaviour and learning-related outcomes were associated with the time of day that university students had their first class. Many students may be forced to make one of two undesirable choices when faced with early class start times: sleep longer instead of attending class or wake up earlier to attend class,” the investigators pointed out.

“Our findings suggest that there might be cumulative negative effects of morning classes on absenteeism and presenteeism that lead to poorer academic achievement,” they said.

Previous studies have shown that starting classes early can be detrimental to sleep and daytime functioning of students. As adolescents and young adults experience a natural delay in their preferred sleep schedule due to biological and environmental factors, those who stay up late and have to wake up early for class may end up with less hours of sleep at night. Additionally, the body’s natural drive for sleep may be at its strongest during the time when students are expected to attend early morning classes. When combined, the effects of inadequate sleep and circadian misalignment can cause daytime sleepiness and impair cognitive performance. [J Adolesc 2018;67:55-65; PLoS ONE 2017;12:e0178782; Sleep Med 2019;60:96-108; PLoS ONE 2015;10:e0128273]

“If the goal of formal education is to position our students to succeed in the classroom and workforce, why are we forcing many university students into the bad decision of either skipping morning class to sleep more or attending class while sleep-deprived?” senior study investigator Associate Professor Joshua Gooley from Duke-NUS’ Neuroscience & Behavioural Disorders Programme commented.

“The take-home message from our study is that universities should reconsider mandatory early morning classes,” Gooley said.

Gooley and colleagues believe that early classes could be scheduled later in the day if classrooms and lecture theatres are not being fully utilized.

“Making classrooms a shared resource across departments might open up time slots for more afternoon/evening courses to be conducted in parallel. To justify taking such actions, universities need scalable methods for assessing the impact of their class scheduling practices on students,” they said.