Impact of the resident duty hours on in-training examination score: A nationwide study in Japan

Abstract

Purpose

The relationship between duty hours (DH) and the performance of postgraduate residents is needed to establish appropriate DH limits. This study explores their relationship using the General Medicine In-training Examination (GM-ITE).

Materials and methods

In this cross-sectional study, GM-ITE examinees of 2019 had participated. We analyzed data from the examination and questionnaire, including DH per week (eight categories). We examined the association between DH and GM-ITE score, using random-intercept linear models with and without adjustments.

Results

Five thousand five hundred and ninety-three participants (50.7% PGY-1, 31.6% female, 10.0% university hospitals) were included. Mean GM-ITE scores were lower among residents in Category 2 (45–50 h; mean score difference, −1.05; p < 0.001) and Category 4 (55–60 h; −0.63; p = 0.008) compared with residents in Category 5 (60–65 h; Reference). PGY-2 residents in Categories 2–4 had lower GM-ITE scores compared to those in Category 5. University residents in Category 1 and Category 5 showed a large mean difference (−3.43; p = 0.01).

Conclusions

DH <60–65 h per week was independently associated with lower resident performance, but more DH did not improve performance. DH of 60–65 h per week may be the optimal balance for a resident's education and well-being.

Keywords:

• General medicine in-training examination
• in-training examination
• postgraduate medical education
• resident duty hours
• resident well-being

Ethical approval

The Ethics Review Board of Juntendo University School of Medicine approved the study.

Acknowledgments

We thank members of JAMEP for their assistance. The authors would like to thank Enago (www.enago.jp) for the English language review.

Disclosure statement

Dr. Nishizaki received an honorarium from the JAMEP as the GM-ITE project manager. Dr. Tokuda and Dr. Okubo are the JAMEP director. Dr. Nagasaki received an honorarium from the JAMEP as a reviewer of GM-ITE. Dr. Kobayashi received an honorarium from the JAMEP as a speaker of the JAMEP lecture. Dr. Shimizu and Dr. Yamamoto received an honorarium from the JAMEP as exam preparers of GM-ITE. Dr. Nishizaki, Dr. Tokuda, Dr. Okubo, Dr. Nagasaki, Dr. Kobayashi, Dr. Shimizu, and Dr. Yamamoto were not involved in the analysis.

Glossary

Duty hours: All clinical and academic activities related to the program, including patient care (both inpatient and outpatient), administrative duties relative to patient care, the provision for transfer of patient care, time spent in-house during call activities, and scheduled activities, such as conferences. Duty hours do not include reading and preparation time spent away from the duty site.¹

Author contributions

Dr. Shinozaki had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Nishizaki and Tokuda: study concept and design. Shinozaki, Shimizu, Yamamoto, and Konishi: acquisition, analysis, or interpretation of data. Nagasaki: manuscript drafting. Nishizaki and Kobayashi: critical revision of the manuscript for important intellectual content. Shinozaki: statistical analysis. Nishizaki and Tokuda: administrative, technical, or material support. Nishizaki, Kobayashi, and Tokuda: supervision.

Data availability statement

Due to the nature of this research, participants of this study did not agree for their data to be shared publicly, so supporting data is not available.

Prior presentations

The results of the study were reported on 5 November 2020, at the ‘Committee on Promoting Reform of the Working Style of Physicians’ organized by the Ministry of Health, Labour and Welfare [https://www.mhlw.go.jp/stf/newpage_14763.html (in Japanese)].

Notes

1 ACGME website. [accessed 2021 Jul 21]. https://www.acgme-i.org/Accreditation-Process/Glossary/.

Additional information

Notes on contributors

Kazuya Nagasaki

Kazuya Nagasaki, MD, works as a staff physician at Mito Kyodo General Hospital.

Yuji Nishizaki

Yuji Nishizaki, MD, MPH, PhD, is an associate professor of medical education at Juntendo University School of Medicine.

Tomohiro Shinozaki

Tomohiro Shinozaki, MPH, PhD, is a Jr. associate professor of biostatistics at Tokyo University of Science.

Hiroyuki Kobayashi

Hiroyuki Kobayashi, MD, PhD, is a professor of medicine at the University of Tsukuba and works as a head of the internal medicine department in Mito Kyodo General Hospital.

Taro Shimizu

Taro Shimizu, MD, PhD, MPH, MBA, is a professor of medicine at Dokkyo Medical University Hospital.

Tomoya Okubo

Tomoya Okubo, PhD, is an associate professor in the department of test analysis and evaluation at the National Center for University Entrance Examinations.

Yu Yamamoto

Yu Yamamoto, MD, is an assistant professor of the division of general medicine at Jichi Medical University.

Ryota Konishi

Ryota Konishi, MD, MS, works as an education advisor at the Japan Organization of Occupational Health and Safety.

Yasuharu Tokuda

Yasuharu Tokuda, MD, MPH, is a director of the Muribushi Okinawa Center for Teaching Hospitals.