The Impact of Physicians' Working Hours on Inappropriate Use of Outpatient Medicine in a Tertiary Hospital in China.

Background: Inappropriate prescribing is an important health system problem in China. Several studies have identified critical factors influencing prescription quality, but the impact of physicians' working hours remains unknown. In China, tertiary hospitals face ever-increasing outpatient volumes. Physicians are asked to work long hours and the impact of shift duration on prescription quality is unknown.

Objective: We aimed to investigate the association between consecutive working hours and the quality of physicians' prescriptions in a Chinese tertiary hospital.

Methods: We obtained all outpatient electronic health records from the hospital information system (HIS) of a tertiary hospital in Beijing, China from 1 July to 30 November 2015. Prescriptions made during two periods were analyzed: a morning shift from 7:30 to 12:30, and an afternoon shift from 13:30 to 18:30. The time when a physician issued the first prescription was considered the beginning of the work shift and prescriptions within the next 4 consecutive hours were included. Potentially inappropriate prescriptions were based on the Rational Drug Use (RDU) system that was developed and validated for this study. We used multivariable logistic regression to examine the impact of shift duration and other clinical and physician factors on potentially inappropriate prescribing.

Results: Of the total 560,529 prescriptions, 15.3% were classified as inappropriate by the RDU system. Physicians' inappropriate prescribing increased in the last hour in each work shift (odds ratio (OR) for the fourth hour compared to the first = 1.12 (95% CI, 1.09-1.15)). We also found that physicians who worked all day had a higher rate of inappropriate prescribing than those who only worked half a day (OR = 1.05 (95% CI, 1.04-1.07)).

Conclusions: Longer working hours are a risk factor for inappropriate prescribing. Relevant interventions are urgently needed to establish working hour limits in China to reduce the likelihood of inappropriate prescribing by physicians.