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Research consis­tently confirms that safe nurse staffing is critical to quality of care and patient safety.

An aging popula­tion, advances in technology and declining lengths of stay have steadily increased patient acuity in hospi­tals. Nursing care requires contin­uous patient assess­ment, critical thinking and expert judge­ment. When staffing levels are too low, RNs are often forced to compro­mise the care they give to their patients.

Unsafe nurse staffing is a dangerous practice that leads to medical errors, poorer patient outcomes and nursing injuries as well as burnout.

Key findings from research studies on safe nurse staffing

The Business of Caring: Promoting Optimal Allocation of Nursing Resources

This article describes the impact of nurse staffing levels on patient outcomes. The impor­tance of improved collab­o­ra­tion between nursing and finance is empha­sized, to build trust and reach a shared under­standing of the relation­ships between cost, quality, and patient experi­ence. Action steps to improve alloca­tion of resources are provided along with an excel­lent list of current references.

Begley, R., Cipriano, P., & Nelson, T. (2020). The business of caring: Promoting optimal alloca­tion of nursing resources. Retrieved from https://​www​.hfma​.org/​c​o​n​t​e​n​t​/​d​a​m​/​h​f​m​a​/​Documents/industry-initiatives/business-of-caring-promoting-optimal-allocation-nursing-resources.pdf

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Patient mortality risk increases by 7% for each additional patient added to a nurse’s workload

Aiken et al., conducted a large cross-sectional analysis of linked data from 10,184 staff nurse surveys, 232,342 surgical patients who were discharged, and admin­is­tra­tive data from 168 hospi­tals to estimate the proba­bility of failure to rescue (deaths within 30 days of admis­sion in patients who experi­enced compli­ca­tions) and mortality (death) risk for each patient under various patient-to-nurse ratios (i.e., 4,6, & 8 patients per nurse).

This study demon­strated a signif­i­cant 7% increased mortality risk for every surgical patient added to the average nurse-patient workload. The mortality risk jumped to 14% when a nurse’s patient load went from 4 – 6 and a 31% mortality risk when that load went from 6 – 8 patients.

This study clearly illus­trates the benefit of adequate staffing and direct corre­la­tion with safe patient outcomes.

Aiken, L. H., Clarke, S. P., Sloane, D. M., Sochalski, J., & Silber, J. H. (2002). Hospital nurse staffing and patient mortality, nurse burnout, and job dissat­is­fac­tion. JAMA, 288(16), 1987 – 1993.

Enhanced nursing work environments, staffing and higher levels of nursing education positively impact risk of patient mortality

A large obser­va­tional study examined the effects of nurse staffing, work environ­ment and nurse educa­tion on patient mortality in 14 high-tech teaching hospi­tals with at least 700 beds. This study linked facility data from each hospital to nurse survey data from 1,024 nurses and discharge data from 76,036 surgical patients.

This study demon­strated a 5% increased risk of mortality with each additional patient per nurse, a 50% decrease in mortality risk in hospi­tals with good versus mixed/​poor nurse environ­ments and a 9% decrease in mortality risk with 10% increase in staff nurses who had a bachelor’s degree in nursing.

Patient outcomes and risk for mortality are linked to a constel­la­tion of key variables.

Cho, E., Sloane, D. M., Kim, E. Y., Kim, S., Choi, M., Yoo, I. Y., … Aiken, L. H. (2015). Effects of nurse staffing, work environ­ments, and educa­tion on patient mortality: an obser­va­tional study. Int J Nurs Stud, 52(2), 535 – 542. doi:10.1016/j.ijnurstu.2014.08.006

Adequate nurse staffing and higher education decrease chances of patient mortality

A cross-sectional data analysis, looking for patient mortality directly associ­ated with missed nursing care and nurse staffing levels, was performed. Combined data from date range 2009 – 2011 was collected on 422,730 surgical patients and from 26,516 regis­tered nurses, in 300 general acute hospi­tals across nine countries.

These results showed that for each additional patient per nurse increase, a patient has a 7% increased risk of dying within 30 days of admis­sion and for every 10% increase in missed nursing care (due to lack of time) there was a 16% increased risk of a patient dying within 30 days.

These are dismal statis­tics, but this study was able to demon­strate that these findings can be mediated when nurse staffing levels are adequate and nurses are more highly educated; for every 10% increase in bachelor’s degree nurses there was a 7% decreased likeli­hood of dying.

Ball, J. E., Bruyneel, L., Aiken, L. H., Sermeus, W., Sloane, D. M., Rafferty, A. M., … Consor­tium, R. N. C. (2018). Post-opera­tive mortality, missed care and nurse staffing in nine countries: A cross-sectional study. Int J Nurs Stud, 78, 10 – 15. doi:10.1016/j.ijnurstu.2017.08.004

Patient activity and acuity have a direct impact on work demands of nurses and are independent risk factors for patient mortality

Needleman and colleagues performed a large cross-sectional study that examined the associ­a­tion between nurse staffing levels and patient mortality.

This study retro­spec­tively analyzed data from 197,961 hospital admis­sions and 176, 696 nursing shifts that were 8 hours in length across 43 hospital units in a tertiary care medical center. The study monitored several other variables that could be associ­ated with patient mortality including units with high shift turnover where there were volumes of admis­sions, trans­fers and discharges that would increase the demands of the nurses.

The results revealed a positive corre­la­tion with patient’s mortality risk where there are high turnover units and nurse staffing well below the target levels and reinforces the critical impor­tance in matching staffing with patients’ needs for nursing care.

Needleman, J., Buerhaus, P., Pankratz, V. S., Leibson, C. L., Stevens, S. R., & Harris, M. (2011). Nurse staffing and inpatient hospital mortality. N Engl J Med, 364(11), 1037 – 1045. doi:10.1056/NEJMsa1001025

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