Effects of the Beginning of the Academic Year on Hospital Mortality: Is the July Phenomenon Real?

Abstract

BACKGROUND It is suggested that in teaching hospitals, mortality rates are higher in the beginning of the academic year (July phenomenon) than in other months of the year. Differences in mortality rates have been reported according to working hours, weekdays, weekends, and off months. The aim of this study was to search for differences in mortality rates in intensive care units or clinics between working hours and night shift hours, weekends and weekdays, and off months and the months when residents start work. MATERIAL and METHODS From a total of 65.535 patients hospitalized in clinics and intensive care units of (blinded for peer review) between April 2009 and May 2015, data from 2.210 patients who died due to any cause were retrospectively evaluated. Patients' exitus frequencies were investigated to find a difference according to working hours/night shift hours, weekends and weekdays, and off months and the beginning of the academic year. RESULTS The rate of mortality in months when residents began to work was 47.3% and that in other months was 52.7% (p=0.98). The risk of mortality in months when residents began to work did not show significant difference compared with other months (Odds Ratio (OR): 1.001, 95% CI: 0.919-1.089; p=0.987). The mortality rate was lower in months when residents begin to work than in other months in the departments of surgical sciences (39.8% vs 60.2%, p=0.03), while the rates were similar in the departments of internal sciences and intensive care units. CONCLUSION The results of this study did not support literature data suggesting that the risk of mortality is higher in months when new residents begin to work in a training and research hospital.