Nurse staffing and nurse outcomes: A systematic review and meta-analysis
Introduction
Hospital nursing staff provides holistic care to patients and their families for 24 hours a day. Suboptimal nurse staffing such as lower staffing levels, greater use of nurse overtime, high use of temporary nursing staff, and high turnover often occur because of nursing shortage (Bae, Kelly, Brewer, & Spencer, 2014). Such suboptimal nurse staffing in hospitals can affect the quality of patient care and nurses' health and well-being (Nantsupawat, Nantsupawat, Kulnaviktikul, & McHugh, 2015).
In recent years, the International Council of Nurses, International Hospital Federation, and other International Health professional associations emphasized a Positive Practice Environments (PPE) campaign to prevent aggravating nursing shortages and to ensure the health, safety, and personal well-being of health professionals including nurses (World Health Organization, 2010). According to the PPE campaign, a safe nurse staffing level, which is one of the elements of PPE in health-care services, leads to a higher retention rate and overall job satisfaction (World Health Organization, 2010). In fact, several countries including South Korea are currently implementing a nurse staffing policy to regulate nurse staffing levels. In the United States, many state legislatures have approved nurse staffing policies that incorporate one or more of the following strategies: (a) mandated nurse-to-patient ratios (California), (b) mandated nurse staffing committees (e.g., Texas), or (c) mandated disclosure of hospital nurse staffing level (e.g., New York) (Jones, Bae, Murry, & Hamilton, 2015). In South Korea, a financial incentive policy on nurse staffing, namely, the nursing fee differentiation policy (NFDP), has been implemented since 1999 (Kim, 2007). This NFDP consists of a seven-nurse staffing grade system, and each grade reflects the average number of bed per nurse in general hospitals (Health Insurance Review & Assessment Service, 2017). All of these nurse staffing policies aim to improve the positive practice environment in health-care services to ensure appropriate levels of nurse staffing.
Nurse staffing is often measured by either staffing level or staffing mix, or both. Nurse staffing levels consist of a total number of nurses or nursing care hours per patient volume (e.g., number of beds or patient days). The nurse-to-patient ratio (or the patient-to-nurse ratio) and the total nursing hours per patient days (NHPPD) are often used to measure nurse staffing level. With respect to staffing mix, registered nurse (RN) staffing ratio is often used to represent the proportion of RNs in the total number of nursing staff, which include RNs, licensed practice nurse (LPN), and nurse aids. It often shows the nursing professional skill mix. Another nurse staffing measure is subjective nurse staffing adequacy using nurses' perception regarding nurse staffing (Aiken, Clarke, & Sloane, 2002). The nurse staffing policy in several countries is implemented based on the nurse-to-patient ratio (e.g., California).
A great number of studies have been conducted to examine the relationship between nurse staffing and patient outcomes. It has been shown that lower nurse-to-patient ratio (better nurse staffing) and RN skill mix are related to better quality of patient care (Aiken et al, 2011, Kalisch et al, 2012, Staggs et al, 2012). Through meta-analysis, Kane and colleagues (Kane, Shamliyan, Mueller, Duval, & Wilt, 2007) have found that increased RN staffing is associated with lower hospital mortality rate, hospital acquired pneumonia, unplanned extubation, respiratory failure, and cardiac arrest in intensive care units. Therefore, relatively conclusive relationships between nurse staffing and patient outcomes have been identified.
With respect to nurse outcomes, researchers have found that lower nurse staffing is associated with higher nurse burnout and job dissatisfaction (Aiken et al, 2008, Kim, 2007, Nantsupawat et al, 2015, Sheward et al, 2005), and intent to leave (Aiken et al, 2012, Cho et al, 2009). Low nurse staffing is also related to needlestick injury (Clarke et al, 2002, Nantsupawat et al, 2015). However, a study of nurses in Finland showed that nurse staffing is not related to job satisfaction and job stress (Tervo-Heikkinen, Kiviniemi, Partanen, & Vehviläinen-Julkunen, 2009). However, to the best of our knowledge, none of the reviews have rigorously or systematically assessed the evidence about the effect of nurse staffing or specific nurse staffing levels on nurse outcomes through meta-analysis. Because of variations in nurse staffing measures among studies, study findings from these studies should be systematically evaluated to draw a conclusion on the relationship between nurse staffing and nurse outcomes.
Therefore, the current review conducted a systematic assessment of empirical studies to examine the relationship between nurse staffing and nurse outcomes. Based on systematic reviews, we found that the majority of studies used the nurse-to-patient ratios to measure nurse staffing. Nurse outcomes included in this study were rather adverse nurse outcomes, including nurse burnout, job dissatisfaction, intent to leave, and needlestick injuries. Thus, we conducted a meta-analysis to determine the association between the nurse-to-patient ratios and the nurse outcomes, mainly nurse injuries and well-being. The results of this study can provide evidence for developing guidelines on the nurse-to-patient ratio in hospitals to prevent adverse nurse outcomes and to promote nurses' health and well-being.
Section snippets
Design
This study reviewed published studies that examined the relationship between nurse staffing and nurse outcomes in hospitals. However, these studies varied in terms of their study design, outcome variables, and analytical approaches. Therefore, only a subset of reviewed articles was included in the meta-analysis. To ensure methodological rigor, a systematic five-step approach was used, and it consisted of problem formulation, literature search, data evaluation, data analysis, and presentation as
Study Characteristics
A total of 52 potentially relevant articles were identified using the search strategy described above, of which 13 cross-sectional studies met the inclusion criteria (Figure 1). Six (46.2%) of these 13 studies used probability sampling. Samples in all studies were drawn from more than one site. Nurse staffing variables were often measured by the nurse-to-patient ratio, which was established by the number of patients the nurses cared for in their last work shift using the nurse survey or by the
Discussion
This review focused on synthesizing studies that examined the relationship between nurse staffing and nurse outcomes. Nurse staffing was measured by the nurse-to-patient ratio and nurse staffing grade. Based on our findings in the meta-analysis, an increase in patient per RN ratio was associated with an increase in the likelihood of three adverse nurse outcomes out of four outcomes. Even if there is an inconsistency regarding the research methods among studies, we found a consistent
Acknowledgments
Editorial support for the manuscript was provided by Ewha Womans University. Dr Jungbok Lee provided statistical analysis and suggestions on draft manuscript.
References (36)
- et al.
Hospital staffing, organization, and quality of care: Cross-national findings
Nurs Outlook
(2002) - et al.
Organizational climate, staffing, and safety equipment as predictors of needlestick injuries and near-misses in hospital nurses
Am J Infect Control
(2002) - et al.
Leadership styles and outcome patterns for the nursing workforce and work environment: A systematic review
Int J Nurs Stud
(2010) - et al.
Factor structure of the Maslach burnout inventory: An analysis of data from large scale cross-sectional surveys of nurses from eight countries
Int J Nurs Stud
(2009) - et al.
Outcomes of variation in hospital nurse staffing in English hospitals: Cross-sectional analysis of survey data and discharge records
Int J Nurs Stud
(2007) - et al.
Effects of nurse staffing and nurse education on patient deaths in hospitals with different nurse work environments
Med Care
(2011) - et al.
Effects of hospital care environment on patient mortality and nurse outcomes
J Nurs Adm
(2008) - et al.
Patient safety, satisfaction, and quality of hospital care: cross sectional surveys of nurses and patients in 12 countries in Europe and the United States
Br Med J
(2012) - et al.
Analysis of nurse staffing and patient outcomes using comprehensive nurse staffing characteristics in acute care nursing units
J Nurs Care Qual
(2014) - et al.
Introduction to meta-analysis
(2009)
Nurse staffing, quality of nursing care and nurse job outcomes in intensive care units
J Clin Nurs
Effects of hospital staffing and organizational climate on needlestick injuries to nurses
Am J Public Health
Integrating Research: A Guide for Literature Reviews
Factors contributing to nursing leadership: A systematic review
J Health Serv Res Policy
Decision aids: are they worth it? A systematic review
J Health Serv Res Policy
Individual determinants of research utilization: A systematic review
J Adv Nurs
Understanding the new statistics: effect sizes, confidence intervals, and meta-analysis
Inpatient Fee in South Korea
Cited by (129)
2024: Moving to a New Reimbursement Model for Nursing
2024, Journal of Perianesthesia NursingThe Nurse Perceived Adequacy of Staffing Scale for general hospital wards: A development and psychometric validation study
2023, International Journal of Nursing Studies AdvancesHealthy Work Environment Standards in Tele-Critical Care Nursing
2023, AACN Advanced Critical Care
The authors declare no conflict of interest.