Impact of Nurse Staffing Levels on Patient Fall Rates: A Retrospective Cross-Sectional Study in General Wards in Japan.

: Falls are common adverse events among hospitalized patients, affecting outcomes and placing a financial burden on patients and hospitals. This study investigated the relationship between nurse staffing/workload and patient falls during hospitalization. : The patients studied were hospitalized in the general wards (excluding pediatrics and obstetrics/gynecology) of 11 National Hospital Organization institutions between April 2019 and March 2020. The data were obtained from the Diagnosis Procedure Combination Work Record and institutional fall reports. The variables used in the analyses included patient conditions, number of hospitalization cases, emergency hospitalizations, surgeries/examinations, disease composition ratio, patient attributes, hospital stay duration, hospital bed size, and nursing time per patient (day and night) on a ward-day basis. Multivariate analysis was performed to determine the effects of these factors on fall events. : A total of 36,209 ward days were analyzed, with falls reported on 2866 days (fall event rate of 9.0%). The mean nursing times per patient were 1.99 h (day) and 1.47 h (night). The nursing time per patient in the fall group compared to the non-fall group showed an odds ratio of 1.19 ( < 0.01) during day shifts and 0.17 ( < 0.02) during night shifts. An increase in nursing time per patient during the night was associated with fewer fall events, whereas during the day, increased nursing time appeared to contribute to more falls. Common background factors that increased nurse staffing and patient falls simultaneously could be suggested to exist during the day. : Increased nursing time was correlated with reduced fall incidence, indicating the need for policy improvements in nurse staffing practices in Japan to enhance patient safety and outcomes. Further research is needed to accumulate evidence reflecting policies regarding nurse staffing.