Relationships between Alternative Nurse Staffing Level Measurements and Nurses' Perceptions of Nurse Staffing Level Adequacy, Fatigue, and Care Quality

Aims. This study examined the influence of nurse staffing level, measured using various methods, on nurses' perceived adequacy of nurse staffing level, fatigue, and nursing care quality. Background. Although previous studies have recommended various methods of measuring nurse staffing level, there is a lack of research that compares different measurement methods or considers nurses' perceptions of staffing level on a daily basis. Methods. We conducted a cross-sectional study using work sampling and the questionnaire method in a general hospital in South Korea from July 18 to August 14, 2022. Results based on responses from 90 nurses and scores of 5,536 inpatients derived from the Korean Patient Classification System were included in the analysis. Results. The average nurse-to-patient ratio a day was 1 : 3.20, and the registered nursing hours per patient day was 2.35. Perceived insufficient nurse staffing and fatigue were higher on weekdays than on weekends (p<0.001). All variables measuring the nurse staffing level affected the nurses' perceived inadequacy of nurse staffing level, fatigue, and nursing care quality, compared to other variables related to nurse staffing level, such as work intensity and demanding nursing hours per nurse (R-2: 0.19-0.31), the nurse-to-patient ratio had the lowest explanatory power in explaining the nurses' perceptions (R-2: 0.14-0.18). Conclusions. Nurse staffing level measurement should consider the acuity of inpatients and nursing care time. Further research is needed to utilize nurses' perceptions of the appropriate nurse staffing level. Implications for Nursing Management. Efforts are required to maintain an appropriate nurse staffing level through continuous monitoring of nurses' perceptions and acuity of inpatients to preserve nurses' alertness during work and improve nursing care quality.