Association between independent practice time and patient outcomes in the emergency department: a retrospective study of residents in three urban hospitals in Taiwan

BACKGROUND: The purpose of the study was to investigate the relationship between the independent practice time of residents and the quality of care provided in the Emergency Department (ED) across three urban hospitals in Taiwan. The study focused on non-pediatric and non-obstetric complaints, aiming to provide insights into the optimal balance between resident autonomy and patient safety. METHODS: A comprehensive retrospective study was conducted using de-identified electronic health records (EHRs) from the hospital's integrated medical database (iMD) from August 2015 to July 2019. The independent practice time was defined as the duration from the first medical order by a resident to the first modifications by the attending physician. The primary outcome was revisits to the ED within 72 h following discharge. Statistical analysis was conducted using RStudio and pyGAM. RESULTS: The study identified several factors associated with shorter independent practice times (< 30 minutes), including older patient age, male sex, higher body temperature, higher heart rate, lower blood pressure, and the presence of certain comorbidities. Residents practicing independently for 30–120 minutes were associated with similar adjusted odds of patient revisits to the ED (OR 1.034, 95% CI 0.978–1.093) and no higher risk of 7-day mortality (OR 0.674, 95% CI 0.592–0.767) compared to the group with less autonomy. However, independent practice times exceeding 120 minutes were associated with higher odds of revisiting the ED within 72 h. For the group with 120–210 minutes of independent practice time, the OR was 1.113 (95% CI: 1.025–1.208, p = 0.011). For the group with > 210 minutes, the OR was 1.259 (95% CI: 1.094–1.449, p = 0.001), indicating an increased risk of adverse outcomes as the independent practice time increasing. CONCLUSIONS: The study concludes that while providing residents an independent practice time between 30 to 120 minutes may be beneficial, caution should be exercised when this time exceeds 120 minutes. The findings underscore the importance of optimal supervision in enhancing patient care quality and safety. Further research is recommended to explore the long-term effects of different levels of resident autonomy on patient outcomes and the professional development of the residents themselves. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12873-023-00877-9.