Influence of nursing time and staffing on medical errors: A cross-sectional analysis of administrative data

Abstract

Background Medical errors cause adverse events; however, no studies have examined medical errors related to nursing hours considering unit characteristics in Japan. We investigated medical errors mainly caused by nurses to quantitatively assess ward activity as busyness in nursing duties. Methods This study considered patients hospitalized in general wards of 10 National Hospital Organization institutions between April 2019 and March 2020. Study data were obtained from the Diagnosis Procedure Combination system, incident reports system, and the format to report nursing staffing and time. Data for 27,629 unit-days with 88,475 patients were analyzed. Multivariate analysis was performed to determine effect of factors on medical errors. Results The mean age of the patients was 71.43 years (SD = 15.08). The medical error rate in the units was 13.71%. The mean nursing time per patient during day shift was 1.95 hours (SD = 0.58) in the non-medical error group and 2.06 hours (SD = 0.58) in the medical error group (p < 0.01). Nursing time per patient in the medical error group compared to that in the non-medical error group had an odds ratio of 1.31 (p < 0.01) during day shift. Conclusions Contrary to the evidence, the results showed that medical errors caused by nurses were related to increased nurse time with patients in day shifts. Further investigation is needed on the relationship of busyness with nursing duties to ensure the adequate nurse-patient ratio and nursing time to improve patient safety.