Students more likely to pass oral exams at noon — and that might apply to job interviews, too

Why Exam Timing Matters: Italian Study Reveals Students Perform Best at Midday

In the world of Italian universities, academic success often hinges on high-stakes oral exams—an evaluative process as nerve-wracking as it is crucial. But a new study suggests that it isn’t just what students know, but when they’re tested that could tip the scales between success and failure.

According to research published in Frontiers in Psychology, students have the highest chance of passing these oral exams around midday. “We show that academic assessment outcomes vary systematically across the day, with a clear peak in passing rates around midday,” said Prof. Carmelo Mario Vicario, director of the Social-Cognitive Neuroscience Lab at the University of Messina and lead author of the study. “Students were more likely to pass in late morning compared to early morning or late afternoon.”

The implications of this discovery may go far beyond university walls. “We believe this pattern could extend to job interviews or any evaluative process scheduled throughout the day,” Vicario added. “We would be very interested in investigating whether hiring decisions, too, fluctuate in fairness or outcome depending on time of day.”

The inspiration for the study came from previous research on judicial decision-making, which found that judges were more lenient after meal breaks. However, that data could have been skewed by the nature of cases being scheduled at different times. Vicario and his team turned to oral university exams—a process that’s less structured and often more subjective—to explore whether time-of-day could directly influence judgment.

“Oral exams in Italian universities are scheduled at set times, typically lasting 10 to 30 minutes per student,” Vicario explained. “There's no standardized format: professors ask questions based on the course content, and grades are assigned on the spot. These exams can be highly stressful due to their unpredictable nature and the strong weight they carry in academic progression.”

The team analyzed a rich dataset from the University of Messina, consisting of 104,552 assessments conducted by 680 examiners across 1,243 courses between October 2018 and February 2020. By factoring in the number of academic credits each exam carried, they were able to account for difficulty levels and isolate the effect of timing.

The findings revealed a surprising bell curve in pass rates. Only 57% of students passed overall, but the likelihood of success spiked at noon. Performance was similarly strong at 11:00 and 13:00, but it dipped sharply in the early morning and late afternoon. A student sitting an exam at 08:00 or 16:00 was at a distinct disadvantage compared to one tested during lunchtime hours.

"These findings have wide-ranging implications,” said co-author Prof. Alessio Avenanti of the University of Bologna. “They highlight how biological rhythms — often overlooked in decision-making contexts — can subtly but significantly shape the outcome of high-stakes evaluations."

Though the study did not identify the exact reasons behind this midday advantage, it aligns with existing research on cognitive performance. Energy and focus tend to peak during the late morning and gradually decline as the day wears on. Meanwhile, professors may also fall victim to decision fatigue, leading to harsher grading in the afternoon.

Another factor could be the mismatch in biological clocks. While university students in their twenties are typically night owls, professors—often in their forties or older—may be morning larks. This misalignment could mean that students are least alert just when professors are most demanding.

“To counteract time-of-day effects, students might benefit from strategies like ensuring quality sleep, avoiding scheduling important exams during personal ‘low’ periods, and taking mental breaks before performance tasks,” Vicario suggested. “For institutions, delaying morning sessions or clustering key assessments in the late morning may improve outcomes.”

Still, the researchers urge caution in drawing definitive conclusions. “While we controlled for exam difficulty, we can’t entirely exclude other unmeasured factors,” said Prof. Massimo Mucciardi, senior author of the study. “We couldn’t access detailed student- or examiner-level data such as sleep habits, stress, or chronotype. This is why we encourage follow-up studies using physiological or behavioral measures to uncover the underlying mechanisms.”

What’s clear, however, is that time matters. As universities and employers alike search for ways to make their evaluations more equitable, considering the clock may be an easy—and powerful—place to start.

 Read the whole research here