Research Linking Safe Patient Limits to Patient Safety

A Repeated Cross-Sectional Study of Nurses Immediately Before and During the COVID-19 Pandemic: Implications for Action

Linda H. Aiken*, Douglas M. Sloane, Matthew D. McHugh, Colleen A. Pogue, Karen B. Lasater, Nursing Outlook, Dec. 2022.

This was a cross-sectional study conducted by the nation’s preeminent researches on the impact of nurses working conditions on patient care and the nursing workforce, which was  based on surveys of 151,335 registered nurses in New York and Illinois, including a subset of 40,674 staff nurses working at 357 hospitals, representing 99% of all facilities in those states. It found:

• Better staffed hospitals before pandemic had better outcomes during it.

• Policies to prevent chronic hospital nurse understaffing are needed.

• Minimum hospital patient/nurse ratio policies recommended.

“Chronic nurse understaffing and poor work environments in hospitals that existed prior to the Covid-19 pandemic and worsened during it are the major explanations for why many hospitals cannot hire and keep enough nurses even though Covid-19 hospitalizations have dropped,” the study authors concluded. 

“Without fundamental improvements in hospital nurse staffing and work environments, the shortage of nursing care in hospitals will not likely abate even after the Covid-19 pandemic has run its course. Increasing the supply of nurses through short-term emergency measures is unlikely to solve the problem. Hospitals need to hire more permanent registered nurses, provide more favorable work environments, and earn back the confidence of nurses that quality and safety of patient care are institutional priorities. Because most hospitals have not implemented substantial improvements in either staffing or work environments over the past decade (Aiken et al., 2018; Sloane et al., 2018), policymakers should mandate hospitals to meet minimum safe nurse staffing standards.” (Emphasis added)

Nurse Staffing and Inpatient Mortality in the English National Health Service: A Retrospective Longitudinal Study

James Bird, Elaine Kelly, Luca Mercuri, Carol Propper, Anne Marie Rafferty , Natalie Jean Sanford, Janice Sigsworth, Mary Wells, Ben Zaranko, BMJ Quality and Safety, September 2022.

A study of 9 287 ward-day observations with information on 4498 nurses and 66 923 hospital admissions in 53 inpatient hospital wards for acutely ill adult patients for calendar year 2017.

“Our study shows that both the level of RN staffing and the seniority mix of RNs were associated with patient mortality outcomes, but HCSW and agency nurse staffing were not.”

Patient Outcomes and Cost Savings Associated With Hospital Safe Nurse Staffing Legislation: An Observational Study

Karen B Lasater, Linda H Aiken, Douglas Sloane, Rachel French, Brendan Martin, Maryann Alexander, Matthew D McHugh, BMJ Open, December 2021.

Researchers at the Center for Health Outcomes and Policy Research at the University of Pennsylvania School of Nursing, conducted independent research on whether a proposed bill in the Illinois state legislature to set a safe nurse staffing standard of no more than 4 patients per nurse is in the public’s interest. The study of 87 hospitals and 210,000 hospitalized patients documented large differences in patient-to-nurse ratios by hospital from 5.4 patients for each nurse in some hospitals to as many as 7.6 patients per nurse in others. The Safe Staffing Limits Act calls for hospital nurses outside of ICUs to care for no more than 4 patients each. The study’s findings suggest that the significant variation in patient-to-nurse ratios across hospitals in Illinois is contributing to avoidable deaths and unnecessary costs.

The study found patient deaths in Illinois hospitals are significantly lower in hospitals with fewer patients per nurse. The study found that each additional patient added to a nurse’s workload is associated with 16% higher deaths. Also, average length of hospital stay is higher in hospitals with worse nurse staffing. Each additional patient added to a nurse’s workload increases by 5% the odds of patients staying a day longer in the hospital, adding millions of dollars each year to hospital costs in the state

The researchers estimated that if all Illinois hospitals staffed now at levels recommended in pending state legislation of not more than 4 patients per nurse on medical and surgical units, more than 1,595 deaths could have been avoided and over $117 million saved per year, just among Medicare patients alone and likely considerably more across all hospitalized patients.

The Association Between Nurse Staffing and Inpatient Mortality: A Shift-Level Retrospective Longitudinal Study

Sarah N Musy, Olga Endrich , Alexander B Leichtle , Peter Griffiths,  Christos T Nakas, Michael Simon, International Journal of Nursing Studies, August 2021.

This longitudinal study used routine shift-, unit-, and patient-level data for three years (2015-2017) from one Swiss university hospital. Data from 55 units, 79,893 adult inpatients and 3646 nurses (2670 registered nurses, 438 licensed practical nurses, and 538 unlicensed and administrative personnel).  

This study suggests a relationship between registered nurses staffing levels and mortality. Higher levels of registered nurses positively impact patient outcome (i.e. lower odds of mortality) and lower levels negatively (i.e. higher odds of mortality).

“Exposure to shifts with high levels of registered nurses had lower odds of mortality by 8.7% [odds ratio 0.91 95% CI 0.89–0.93]. Conversely, low staffing was associated with higher odds of mortality by 10% [odds ratio 1.10 95% CI 1.07–1.13].”

Effects of Nurse-to-Patient Ratio Legislation on Nurse Staffing and Patient Mortality, Readmissions, and Length of Stay: A Prospective Study In a Panel of Hospitals

Matthew D McHugh, Linda H Aiken , Douglas M Sloane, 2Carol Windsor , Clint Douglas , Patsy Yates, Lancet, May 2021.

In 2016, Queensland (Australia) implemented minimum nurse-to-patient ratios in selected hospitals. We aimed to assess the effects of this policy on staffing levels and patient outcomes and whether both were associated. This study compared nurse staffing and patient outcomes between hospitals with mandated ratios to those without and found hospitals with established patient limits for nurses had lower mortality, fewer preventable readmissions, and a shorter length of stay. 

“Minimum nurse-to-patient ratio policies are a feasible approach to improve nurse staffing and patient outcomes with good return on investment,” the researchers concluded. 

Is Hospital Nurse Staffing Legislation in the Public’s Interest? An Observational Study in New York State

Lasater, Karen B. PhD, RN; Aiken, Linda H. PhD, RN, FAAN; Sloane, Douglas M. PhD; French, Rachel BSN, RN*; Anusiewicz, Colleen V. PhD, RN; Martin, Brendan Ph; Reneau, Kyrani MS; Alexander, Maryann PhD, RN, FAAN; McHugh, Matthew D. PhD, RN, FAAN, , Medical Care, May 2021.

Researchers at the Center for Health Outcomes and Policy Research (CHOPR) at the University of Pennsylvania School of Nursing, conducted independent research in early 2020 on whether pending nurse staffing legislation in New York state is in the public’s interest. The study of 116 hospitals and 418,000 Medicare patients documented large differences in patient-to-nurse ratios by hospital from an average of 4.3 patients for each nurse to as many as 10.5 patients per nurse. The wide variation in patient-to-nurse ratios across hospitals in New York is contributing to avoidable deaths and unnecessary costs.

The new study finds hospital deaths and costs of care are significantly lower in hospitals with better nurse staffing. Each additional patient added to a nurse’s workload is associated with 13% higher in-hospital mortality and 8% higher readmissions. Similarly, the odds of staying a day longer in the hospital, a major cost factor, increased by 9% for surgical patients and 5% for medical patients.

“Were hospitals staffed at the 4:1 P/N ratio proposed in the legislation, we conservatively estimated 4370 lives saved and $720 million saved over the 2-year study period in shorter lengths of stay and avoided readmissions.”

Staffing Levels and Nursing Sensitive Patient Outcomes: Umbrella Review and Qualitative Study

Kai Svane Blume Msc, Uta Kirchner-Heklau Msc, Vera Winter PhD, Steffen Fleischer PhD, Lisa Maria Kreidl Msc, Gabriele Meyer PhD, Jonas Schreyögg PhD,Health Services Research, March 2021.

This study screening 430 potentially relevant records, and 15 literature reviews that addressed the link between nurse staffing and a variety of nurse sensitive patient outcomes. 

We identified strong evidence for a significant association between nurse staffing levels and nurse sensitive patient outcomes including patients’ length of stay in the hospital and patient readmissions.

“…fewer nurses likely increase the probability that patients do not feel cared for with an adequate amount of time or attention. One explanation for the strong evidence for length of stay and readmission could be that nurses facing understaffing might be less likely to detect complications or new health problems at early stages. Such complications might increase length of stay or become apparent and worsen after discharge, ultimately necessitating readmission,” the authors concluded. 

Chronic Hospital Nurse Understaffing Meets COVID-19: An Observational Study        Lasater KB, Aiken LH, Sloane DM, et al. BMJ Qual Saf. 2021;8(8):639-647.BMJ Quality and Safety, August 2020.

This study used survey data from nurses and patients in 254 hospitals in New York and Illinois between December 2019 and February 2020 to determine the association between nurse staffing and outcomes, patient experience, and nurse burnout. A significant number of nurses who experienced burnout viewed their hospitals’ safety unfavorably and would not recommend their hospital. Analyses indicated that each additional patient per nurse increased the odds of unfavorable reports from nurses and patients and demonstrates the implications of understaffing, even before COVID-19. 

“Hospital nurses were burned out and working in understaffed conditions in the weeks prior to the first wave of COVID-19 cases, posing risks to the public’s health. Such risks could be addressed by safe nurse staffing policies currently under consideration,” the authors concluded.

A Meta-Analysis of the Associations Between the Nurse Work Environment in Hospitals and 4 Sets of Outcomes
Lake, Eileen T., PhD, RN, FAAN*; Sanders, Jordan, BSN†; Duan, Rui, MS‡; Riman, Kathryn A., BSN, BSPH, RN*; Schoenauer, Kathryn M.*; Chen, Yong, PhD‡    Published online Medical Care: March 22, 2019  Publication Date: 2019/05/01.  Medical Care. 57(5):353–361, MAY 2019   DOI: 10.1097/MLR.0000000000001109
PMID: 30908381

A new meta-analysis from Penn Nursing’s Center for Health Outcomes & Policy Research (CHOPR) has synthesized 16 years of studies to show the association between the nurse work environment and four sets of outcomes: nurse job outcomes, nurse assessments of quality and safety, patient health outcomes, and patient satisfaction. This important new study integrates extensive research articles reflecting data from 2,677 hospitals, 141 nursing units, 165,024 nurses, and 1,368,420 patients in 22 countries. Researchers report consistent, significant associations between the work practice environment and all four major outcomes listed above. The study authors concluded that the nurse work environment warrants attention to promote health care quality, safety, and patient and clinician well-being. They note that nurses play critical roles in patient safety and are often the last line of defense against medical errors and unsafe practices:

“Our quantitative synthesis of the results of many studies revealed that better work environments were associated with lower odds of negative outcomes ranging from patient and nurse job dissatisfaction to patient mortality,” said lead-investigator Eileen T. Lake, PhD, MSN, FAAN, the Jessie M. Scott Endowed Term Chair in Nursing and Health Policy.

The researchers’ systematic review of these studies from around the world reported empirical research using the Practice Environment Scale of the Nursing Work Index.

In particular, the researchers noted the following:

A meta-analysis published a decade ago demonstrated consistent associations of staffing ratios to a range of patient outcomes.37 Lower ratios of patients-per-nurse were associated with lower odds of adverse events such as patient mortality and hospital acquired infections, as well as shorter lengths of stay.


Professional organizations, such as the American Association of Critical-Care Nurses (AACN) have encouraged nurses to assess if their work environment is healthy. The AACN presented 6 standards: skilled communication, true collaboration, effective decision making, appropriate staffing, meaningful recognition, and authentic leadership.

Patient Satisfaction with Hospital Care and Nurses in England: An Observational Study
Aiken, Linda H., Douglas M Sloane, Jane Ball, Luk Bruyneel, Anne Marie Rafferty, Peter Griffiths. 2018. BMJ. Published online January 11, 2018. BMJ Open 2018;8:e019189. doi:10.1136/ bmjopen-2017-019189

Patients’ perceptions of hospital care are most strongly associated with missed nursing care, which in turn is related to poor professional (RN) staffing and poor hospital work environments. Improving RN staffing holds promise for enhancing patient satisfaction.  An internationally renowned team of researchers from the University of Pennsylvania, University of Southampton, and King’s College London conducted this large study of 66,348 patients in the U.K. to determine the association between patients’ confidence in nurses and doctors, registered nurse staffing and patient experiences and satisfaction. Researchers found the availability of sufficient numbers of registered nurses in hospitals was the factor most affecting patient satisfaction. Author Linda Aiken, PhD, RN, Director of the Center for Health Outcomes and Policy Research at the University of Pennsylvania: “Patients value nurses so much that when nurses are in short supply, patients’ overall ratings of their hospitals decline sharply.” The nursing care most often reported as missed due to inadequate RN staffing includes: comfort/talk with patients, patient education, updating/development of nursing care plans, adequate patient surveillance, documentation of patient care, oral hygiene, frequent changing of patient position, care planning, administering medications on time, skin care, preparing patients and families for discharge, treatments and procedures and pain management.

Factors Associated with the Removal of Urinary Catheters After Surgery
Catherine Y. Read, PhD, RN; Judith Shindul-Rothschild, PhD, RN; Jane Flanagan, PhD, RN, ANP-BC, AHN-BC; Kelly D. Stamp, PhD, RN, ANP-C, CHFN, FAHA. Journal of Nursing Care Quality: Post Author Corrections: August 24, 2017  doi: 10.1097/NCQ.0000000000000287

This study which included 59 Massachusetts hospitals, found significant association between better nursing staffing and patient outcomes. Removing indwelling urinary catheters within 48 hours of surgery is an evidence-based strategy to prevent catheter-associated urinary tract infections (CAUTI), a complication that leads to patient distress and decreased reimbursement for hospitals from CMS. Publicly available data from the Centers for Medicaid & Medicare Services were used to analyze factors associated with removal of the urinary catheter within 48 hours after surgery in 59 Massachusetts hospitals. Three factors explained 36% of the variance in postoperative urinary catheter removal: fewer falls per 1,000 discharges, better nurse-patient communication, and higher percentage of Medicare patients. Timely urinary catheter removal was significantly greater in hospitals with more licensed nursing hours per patient.

Beyond the Pain Scale: Provider Communication and Staffing Predictive of Patients’ Satisfaction with Pain Control
Shindul-Rothschild J1, Flanagan J2, Stamp KD2, Read CY2, Pain Manag Nurs. 2017 Dec;18(6):401-409. doi: 10.1016/j.pmn.2017.05.003. Epub 2017 Aug 23.

This study of hospitals in Massachusetts, California and New York, found that patients’ satisfaction with pain management is linked to nurse staffing. Given the opioid crisis, pain management is front and center in health care today,” the authors stated.” We need to think critically of how we are managing pain, how we are communicating with patients, and how members of treatment teams are communicating with each other.” Findings from the study support nurses as key contributors to patient satisfaction with pain control and highlight the need for adequate numbers of nursing staff to achieve optimal patient satisfaction with pain management.“

Nurse Staffing and Hospital Characteristics Predictive of Time to Diagnostic Evaluation for Patients in the Emergency Department.
Shindul-Rothschild J1, Read CY2, Stamp KD2, Flanagan J2, J Emerg Nurs. 2017 Mar;43(2):138-144. doi: 10.1016/j.jen.2016.07.003. Epub 2016 Oct 20.

This groundbreaking study of Massachusetts hospitals shows that the number of patients emergency department (ED) nurses care for is directly related to how long patients wait for treatment.  The study found wait times in trauma EDs for diagnostic evaluation double for every three additional patients an emergency nurse cares for in 24 hours, according to the study’s analysis of 15 Massachusetts hospital trauma EDs. Three patients added to a non-trauma ED nurse’s assignments means an extra 15 minutes waiting for evaluation. “We already know that Massachusetts emergency departments are overcrowded and patients are struggling with excessive wait times,” according to lead author Boston College Associate Professor Judith Shindul-Rothschild, PhD, MSN, RN “the best way to significantly lower patient wait times is to adequately staff our EDs with registered nurses.”

Predictors of 30-Day Readmission for Pneumonia
Flanagan J1, Stamp KD, Gregas M, Shindul-Rothschild J., J Nurs Adm. 2016 Feb;46(2):69-74

This study examined variances in outcome measures associated with 30-day pneumonia readmissions from 577 nonfederal general hospitals in Massachusetts, California, and New York from 4 sources: number of hospital-acquired conditions, patient perception of care, quality outcome measures, and demographic data to explain variances associated with 30-day pneumonia readmission rates. Patients readmitted within 30 days for pneumonia increases the length of hospital stay by 7 to 9 days, increases crude mortality rate 30% to 70%, and costs  $40,000 or greater per patient. Results: Three factors increased pneumonia readmission rates: poor nurse-patient communication, poor staff responsiveness to patient needs, and iatrogenic pneumothorax. Conversely, factors lowering pneumonia readmission rates included patients hospitalized in California, where there is higher RN staffing, and higher proportions of nursing staff to total hospital personnel. Conclusion: Findings suggest lower nurse staffing, poor nurse-patient communication, and nurse responsiveness to patient needs contribute to increased pneumonia readmission rates.

Comparison of the Value of Nursing Work Environments in Hospitals Across Different Levels of Patient Risk
Silber, Jeffrey H., MD, PhD; Paul R. Rosenbaum, PhD; Matthew D. McHugh, PhD, JD, RN, MPH; Justin M. Ludwig, MA; Herbert L. Smith, PhD; Bijan A. Niknam, BS; Orit Even-Shoshan, MS; Lee A. Fleisher, MD; Rachel R. Kelz, MD, MSCE: Linda H. Aiken, PhD, RN. 2016. JAMA Surg. Published online Jan. 20, 2016.  Doi:10.1001/jamasurg2015.4908

There is a 20% lower risk that a patient will die within 30 days of having general surgery at a hospital with above average nurse staffing levels, defined in this study as facilities that had a mean ratio of about 1.5 nurses per bed vs. those with a mean of less than one nurse per bed. Results were based on outcomes and cost of care of a total of 172,225 patients in 606 hospitals across 3 states (Illinois, New York and Texas) between 2004 and 2006.  The greatest benefit from better nurse staffing accrued to the sickest patients who were receiving the riskiest surgeries. The better the nurse staffing by the hospital, the less likely patients were to die and they had a “dramatically lower rate of [costly] ICU (Intensive Care Unit) use.” Moreover, the total cost of surgery remained at about $27,000 in either environment (better or worse nurse staffing). That means the better-staffed facilities had “a formula for excellent value,” said lead study author, Dr. Jeffrey Silber, director of the Center for Outcomes Research at the Children’s Hospital of Philadelphia. “Identifying hospitals with good nursing environments and staffing levels makes sense (for patients),” he said. “The findings that patients undergoing general surgery at hospitals with better nursing environments generally receive a higher value of care and the outcomes would likely be similar today as the characteristics of hospitals studied have not changed greatly.”

Commentary:  Revisiting Nursing’s Effect on Surgical Quality and Cost
Amir A. Ghaferi, MD, MS; Christopher R. Friese, PhD, RN, AOCN Invited Commentary JAMA Surg. January 20, 2016.

The term “culture of safety” has become commonplace within U.S. healthcare facilities, yet many still struggle to create the infrastructure needed to drive an integrated safety system. “Thoughtful coordination of all the players” through teamwork, communication and leadership, are key to improving patient safety and quality, and lowering costs,” wrote Dr. Amir Ghaferi and Christopher Friese of the University of Michigan’s Center for Healthcare Outcomes & Policy in invited commentary accompanying this study  above. The authors note that hospitals with better nursing environments have a nearly 20% lower failure-to-rescue rate than control hospitals with poorer staffing, as well as lower ICU length of stay.

Better Nurse Staffing and Nurse Work Environments Associated With Increased Survival of In-Hospital Cardiac Arrest Patients
McHugh, Matthew D., PhD, JD, MPH, RN, FAAN; Monica F. Rochman RN, PhD; Douglas M. Sloane, PhD; Robert A. Berg, MD; Mary E. Mancini, RN, PhD, NE-BC, FAHA, FAAN; Vinay N. Nadkarni, MD, MS; Raina M. Merchant, MD, MSHP; Linda Aiken,  PhD, FAAN, RN; and American Heart Association’s Get  With The Guidelines-Resuscitation Investigators. 2016.  Medical Care Vol 54[1]:74-80.

This major study published in the journal Medical Care (January, 2016) shows that patients who suffer a heart attack while in the hospital are more likely to survive in those facilities where nurses have safe patient assignments and higher RN staffing levels. The authors found that for every patient added to a nurse’s workload, the likelihood of a patient surviving cardiac arrest decreases by five percent per patient.  Moreover, patients cared for in hospitals with poor work environments (where nurses had less autonomy over their practice and resources and weaker relationships and communication with physicians) had a 16% lower likelihood of survival after a heart attack in the hospital. The study included over 11,000 patients over a two-year period in 75 hospitals in 4 states across the country (Pennsylvania, New Jersey, Florida and California) and focused on only those hospitals with an incidence of more than 10 cardiac arrest events during the time period under study. The authors also noted that due to improved staffing standards now generally in place in ICU environments, patients’ odds of survival have stabilized, in contrast to medical-surgical environments where staffing varies substantially across hospitals and so more demonstrably affects survival rates.  This study is the latest in a series of studies showing a direct link between nurses’ workload and patient safety and underscores the need for legislation pending in the Massachusetts legislature, The Patient Safety Act, which would ensure a safe standard of care and safe patient assignments for all patients and all nurses in Massachusetts hospitals.

Nurse Staffing Levels and Patient-Reported Missed Nursing Care
Dabney, Beverley Waller, PhD RN and Beatrice J. Kalisch, PhD RN FAAN. 2015. Vol. 30[4]: 306-312. Oct0ber-December.

This new study by distinguished nursing researchers studies the “large amount of missed [nursing] care” which has been previously documented in a number of recent research studies. The authors found the most frequently reported care that nurses were unable to perform due to inadequate staffing to be ones which “diminish the quality of care and lead to poor outcomes.”  Important nursing activities such as delivering timely medications, repositioning a patient, helping the patient to ambulate (which is key to preventing blood clots and other complications such as pneumonia), mouth care, patient teaching and assessing the effectiveness of medications are often not performed at all or with unwarranted delays that can be as harmful as commissions of errors – because of inadequate RN staffing levels. This study was conducted in three Midwestern hospitals, with a sample of 459 nurses; it validates a 2011 study of 42,888 nursing staff members on 110 patient care units (Kalisch BJ, Tschannen D, Lee KH. Do staffing levels predict missed nursing care? Int J Qual Health Care. 2011; 23(3): 302-308.)

Patient Mortality Is Associated With Staff Resources and Workload in the ICU: A Multicenter Observational Study
Neuraz, Antoine, MD, MSc et al. Critical Care Medicine. 2015. Vol. 43[8]: 1587-1594 August. DOI: 10.1097/CCM.0000000000001015.

A multilocational longitudinal study of 8 ICUs in 4 university hospitals, total 5,718 patient days in Lyon France, where 2 of the ICUs were medical, 4 surgical and 2 mixed medical-surgical. Researchers found evidence-based thresholds for patient to caregiver ratios linked to ICU mortality over time. The researchers examined both RN to patient ratios and MD to patient ratios. The risk of death was increased by a factor of 3.5 (95% CI, 1.3-9.1) when the patient to nurse ratio was greater than 2.5; and it was increased by a factor of 2.0 (95% CI, 1.3-3.2) when the patient to physician ratio exceeded 14. The presence of medical residents did not influence mortality outcomes. The highest ratios occurred more frequently during the weekend for nurses and during the night for physicians. High patient turnover and the volume of life-sustaining procedures performed by staff were also associated with increased morbidity. The study authors note that real-time monitoring of staffing levels and workload with dedicated alarms (to provide safety alerts) is feasible.

Nurse-Physician Collaboration and Hospital-Acquired Infections in Critical Care
Boev, Christine RN, PhD, CCRN and Yinglin Xia, PhD, MS.  Critical Care Nurse. 2015.Vol. 35[2]: 66-72. April.

This longitudinal study found that Intensive Care Units with higher nursing hours per patient day were associated with a .42 decrease in the rate of CLABSI (central line (central catheter)-associated bloodstream infections (P=.05). In addition, the incidence of ventilator-associated pneumonias (VAPs) was examined and an association found between a higher proportion of certified nurses (defined as nurses with certification such as CCRN, oncology nurse and Advanced Trauma Life Support) with a 0.17 lower rate of pneumonia. CLABSIs and VAPs are two of the most common healthcare associated infections and both are associated with increased patient morbidity and mortality. The authors estimate the enormous costs of these healthcare-associated infections (HAIs) to be enormous, with CLABSIs contributing to 30,665 deaths per year and ventilator-associated pneumonias with 35,967 deaths per year.  The setting of the study was a large (750-bed) hospital in western New York. Over the course of the research a total of 671 ICU nurse perception surveys were collected, with an extremely high response rate of 96%. The study authors also found that improved nurse-physician communication and collaboration was significantly related to a lower rate of healthcare-associated infections.

The Impact of Hospital and ICU Organizational Factors on Outcome in Critically Ill Patients: Results from the Extended Prevalence of Infection in Intensive Care Study
Sakr, Yasser MD, PhD et al.; on behalf of the Extended Prevalence of Infection in Intensive Care Study Investigators (EPIC II). 2015. Critical Care Medicine. Vol. 43:3 519-526. March.

This new study, reported at a recent Society of Critical Care Medicine meeting, shows that a nurse to patient ratio of more than 1: 1/5 in an intensive care unit (ICU) was associated with lower in-hospital deaths compared to a 1:2 ratio. The study data is from 2007 and included over 13,000 adults in over 1,200 ICUs in 75 countries, the majority in Western Europe. About 60% of the participating centers were university hospitals. Overall ICU mortality rate was 18.2%. The study validates the intent of a law passed by the Massachusetts legislature last June which mandates the U.S.’s strictest standard for ICU staffing, calling for a standard limit of one patient per nurse, with the option of assigning a second patient to a nurse only under specific circumstances as determined by the nurses in the ICU. Researchers found that assigning a second patient to a nurse increases the risk of death on those units. Investigators attributed the higher mortality rate resulting from lower RN staffing levels to an increase in the likelihood of mistakes from the creation of a stressful environment with distractions and interruptions that adversely affect quality of care. The U.S. ranked 11th in average nurse to patient ratio (Brazil was tops followed by France, Germany, Spain and Belgium).

Predictors of Excess Heart Failure Readmissions: Implications for Nursing Practice
Stamp, Kelly D. PhD, ANP-C; Flanagan, Jane PhD, ANP-BC; Gregas, Matt PhD; Shindul-Rothschild, Judith PhD, RNPC, Journal of Nursing Care Quality: April/June 2014 – Volume 29 – Issue 2 – p 115–123

This study for the first time provided concrete, peer-reviewed data comparing standards of nursing care and patient outcomes for hospitals in Massachusetts, where there is no limit on nurses’ patient assignments, and California, where such a law has been in place for nearly 14 years.  The study provides conclusive evidence that Massachusetts hospital nurses are caring for significantly more patients than their counterparts in California and that patients in Massachusetts are receiving over three hours less care per day from registered nurses than patients on the West Coast (just over six hours of care for patients in our hospitals vs. over nine hours of care per day in California).  As a result, the study found an association between nurse staffing in Massachusetts and a higher rate of readmissions for heart failure.  The authors point out that heart failure is most common and the most expensive condition for which patients are admitted to hospitals, and the number one cause of death in America. 

Should Hospitals Keep Their Patients Longer? The Role of Inpatient and Outpatient Care in Reducing Readmissions
Bartel, Ann P., Carri W. Chan and Song-Hee (Hailey) Kim. 2014. Working Paper 20499, published online by NBER. National Bureau of Economic Research. September.

This new study finds that that longer inpatient hospital stays can save lives and prevent costly hospital readmissions, saving the system millions of dollars. The study calls into question the movement by hospitals to move to outpatient care and/or to place patients in short-stay observation units, a trend that has accelerated with the advent of Accountable Care Organizations. Nurses have seen a number of Massachusetts hospitals cut staffing and inpatient services, while promoting the value of increasing outpatient care, a strategy that this study shows may be short sighted, costly and dangerous. It is also notable that Massachusetts hospitals rank among the worst nationally for patient readmissions due to poor care. The authors analyzed data for 6.6 million Medicare patients hospitalized between 2008 and 2011.

Human Capital and Productivity in a Team Environment: Evidence from the Healthcare Sector
Bartel, Ann P., Nancy D. Beaulieu, Ciaran S. Phibbs, and Patricia W. Stone.  April 2014. “Human Capital and Productivity in a Team Environment: Evidence from the Healthcare Sector.” American Economic Journal: Applied Economics, 6(2): 231-59. DOI: 10.1257/app.6.2.231

More experienced nurses deliver better patient care and shorten the length of stay.  This new study demonstrates the patient safety and economic benefits of proper RN staffing on hospital units. In this case, units staffed with more experienced nurses who work on those units day in and day out has shorter hospital stays for patients with better outcomes.  This study underscores the value of the MNA’s efforts to encourage full and safer staffing of hospital units; for policies and contract language that encourage nurse retention and seniority rights, and for language that limits or prohibits widespread floating of nurses.  Conversely, the study is an indictment of current staffing practices by hospital and nursing administrators, where units are staffed with temporary nurses; where units are purposefully understaffed and nurses are floated to unfamiliar units to care for patients for which they are ill prepared to provide quality care.

Evidence-Based Research Showing Impact of RN Staffing on Patient Outcomes and Health Care Costs.
Linda H. Aiken PhD, et al. The Lancet, Early Online Publication, 26 February 2014.

Study links nurses’ workload and education to patients’ survival after surgery, finding a direct link between nurses’ patient loads and patient deaths following a number of common surgeries. Researchers analyzed responses from more than 26,500 nurses and reviewed medical records for 422,730 patients 50 years or older discharged after common surgeries such as hip or knee replacement, appendectomy, gall bladder surgery, and vascular procedures in nine European countries (Belgium, England, Finland, Ireland, the Netherlands, Norway, Spain, Sweden, and Switzerland). Writing in a linked comment, Alvisa Palese from the University of Udine in Italy and Roger Watson from the University of Hull in the UK say: “The study by Aiken and colleagues provides evidence in favor of appropriate nurse-patient ratios and also provides support for graduate education for nurses. According to Aiken, “Our data suggest that a safe level of hospital nursing staff might help to reduce surgical mortality.”

Hospitals With Higher Nurse Staffing Had Lower Odds of Readmission Penalties Than Hospitals With Lower Staffing.
McHugh, Matthew D., Berez, Julie et al., Health Affairs, October 2013.

Hospitals with higher nurse staffing had 25 percent lower odds of preventable readmissions compared to otherwise similar hospitals with lower staffing. “Investment in nursing is a potential system-level intervention to reduce readmissions that policy makers and hospital administrators should consider in the new regulatory environment as they examine the quality of care delivered to U.S. hospital patients.

An Observational Study of Nurse Staffing Ratios and Hospital Readmission Among Children Admitted for Common Conditions
Heather L. Tubbs-Cooley, Jeannie P. Cimiotti, Jeffrey H. Silber, Douglas M. Sloane, Linda H. Aiken, BMJQS, BMJ Qual Saf published online May 7, 2013.View at

Reducing the patient load for nurses (also known as the patient-to-nurse ratio) dramatically improves care for patients, and reduces the risk for a number of complications.  Excessive patient assignments for nurses (anything above four patients per nurse) results in a significant increase in the risk for children being readmitted to the hospital due to inadequate care and patient education.  For children with medical conditions, every patient assigned to a nurse above four resulted in an 11 percent increased risk for readmission; and for children recovering from basic surgeries, each additional patient assigned to a nurse increased the risk of readmission by a shocking 48%.  This study builds on earlier research published in JAMA for adult patients, which found that for every patient assigned to a nurse above the recommended four patients resulted in a 7 percent increase in the risk of death for those patients. 

A Phased Cluster-Randomized Trial of Rural Hospitals Testing a Quality Collaborative to Improve Heart Failure Care
Robin P. Newhouse, PhD, Cheryl Dennison Himmelfarb, PhD, Laura Morlock, PhD, Kevin D. Frick, PhD, Peter Pronovost, MD, PhD, and Yulan Liang, PhD. Medical Care, Vol. 51, No. 5, May 2013.

Robert Wood Johnson Foundation (RWJF) funded study of 23 rural hospitals in the Eastern United States which found that rural hospitals with lower nurse turnover are more likely to implement all four measures that are central to optimal care for heart failure patients. Metrics examined were: smoking cessation counseling; instructions to patients being discharged from the hospital; assessing how well the heart pumps; and ensuring the patient receives proper medications. Better nurse practice environments were associated with better assessment of how well the heart pumps. Ensuring that heart failure patients receive optimal care can be difficult, particularly in rural hospitals. Rural hospitals discharge nearly a quarter of all heart failure patients, but patients in rural settings, who have little choice as to where they receive care, are least likely to get the recommended care. Researchers found that hospitals with lower nurse turnover and better practice environments implemented more of the measures. The Interdisciplinary Nursing Quality Research Initiative is funded by the Robert Wood Johnson Foundation. To learn more, visit, or follow on Twitter at @INQRIProgram.

The Effects of Nurse Staffing on Hospital Financial Performance: Competitive Versus Less Competitive Markets
Everhart D, Neff D, Al-Amin M, et al., Health Care Manage. Rev. April-June 2013

Nurse staffing levels have a positive association with positive financial performance in competitive hospital markets. Hospitals should reconsider reducing nursing staff, since this is inefficient and can negatively affect financial performance.

Hospital Nursing and 30-Day Readmissions Among Medicare Patients With Heart Failure, Acute Myocardial Infarction, and Pneumonia.
Matthew D. McHugh, PhD, JD, MPH, RN and Chenjuan Ma, PhD, RN, Medical Care, Vol. 51, No. 1, January 2013 52-59

Study results suggest that improving nurses’ work environment and reducing nurses’ workload could result in fewer readmissions for Medicare beneficiaries with common medical problems. Analysis of linked data from California, New Jersey and Pennsylvania shows that each additional patient per nurse in the average nurse’s workload was associated with a 7% higher odds of readmission for heart failure, 6% higher for pneumonia and 9% higher for myocardial infarction patients.

On the basis of the researchers’ estimates, it would be expected that hospitals which improve their work environments could expect their readmission rate to decline from roughly the 84th percentile to the 50th or the 50th to the 16th in the distribution of hospitals studied. Hospitals which would reduce their nurse workload from 6 to 4 patients per nurse would all else being equal, see their readmission rates reduced from 25 to 21%. Research was funded by National Institute on Aging, RWJ Foundation, Penn Institute on Urban Research and others.

Contradicting Fears, California’s Nurse-to-Patient Mandate Did Not Reduce the Skill Level of Nursing Workforce in Hospitals
Matthew D. McHugh, Lesly A. Kelly, Douglas M. Sloane, and Linda H. Aiken, Health Affairs July 2011

The study provides important data about the impact on RN staffing and patient care following the implementation of the California staffing law in 2004. The study found that California hospitals have significantly increased the number of registered nurses compared to other states, while dramatically increasing patient access to professional RN care, a factor long associated with positive patient outcomes in a broad range of care barometers. In the study, the authors highlight the cost benefits for hospitals under new health reform initiatives. “The costs associated with increasing the number of nurses employed in hospitals may be offset by the costs of avoided poor outcomes and adverse events,” the author states. “The potential for offsets and savings may be increased as value-based purchasing programs are implemented in response to the Affordable Care Act of 2010. For example, higher nurse staffing levels have been associated with fewer of the hospital-acquired conditions and infections that the Centers for Medicare and Medicaid Services no longer pays for, unless the complication was present when the patient was first admitted to the hospital.

Quality and Cost Analysis of Nurse Staffing, Discharge Preparation, and Postdischarge Utilization
Marianne E. Weiss, Olga Yakusheva, and Kathleen L. Bobay Health Research and Educational Trust, April 2011

This study extends previous health services research on the impact of nurse staffing on patient outcomes of hospitalization by linking the unit-level nurse staffing directly to postdischarge readmission and indirectly through discharge teaching process to patient readiness for discharge and subsequent ED visits. Findings support recommendations to (1) monitor and manage unit-level nurse staffing to optimize impact on postdischarge outcomes, (2) implement assessment of quality of discharge teaching and discharge readiness as standard predischarge practices, and (3) realign payment structures to offset costs of increasing nurse staffing with costs avoided through improved postdischarge utilization.

Nurse Staffing Effects on Patient Outcomes
Mary A. Blegen, PhD, RN, FAAN,* Colleen J. Goode, PhD, RN, FAAN,w, Joanne Spetz, PhD,* Thomas Vaughn, PhD,z and Shin Hye Park, MS, RN, PhD(c)*, April 2011

Total hours of nursing care determined per inpatient day (TotHPD) in general units was associated with lower rates of congestive heart failure mortality (P<0.05), failure to rescue (P<0.10), infections (P<0.01), and prolonged length of stay (P<0.01). RN skill mix in general units was associated with reduced failure to rescue (P<0.01) and infections (P<0.05). TotHPD in intensive care units was associated with fewer infections (P<0.05) and decubitus ulcers (P<0.10). RN skill mix was associated with fewer cases of sepsis (P<0.01) and failure to rescue (P<0.05). Safety-net status was associated with higher rates of congestive heart failure mortality, decubitus ulcers, and failure to rescue.

Nurses’ Work Schedule Characteristics, Nurse Staffing, and Patient Mortality
Alison M. Trinkoff 4 Meg Johantgen 4 Carla L. Storr 4 Ayse P. Gurses 4 Yulan Liang 4 Kihye Han, February 2011

Work schedule was related significantly to mortality when staffing levels and hospital characteristics were controlled. Pneumonia deaths were significantly more likely in hospitals where nurses reported schedules with long work hours (odds ratio [OR] = 1.42, 95% confidence interval [CI] = 1.17Y1.73, p G .01) and lack of time away from work (OR = 1.24, 95% CI = 1.03Y1.50, p G .05). Abdominal aortic aneurysm was also associated significantly with the lack of time away (OR = 1.39, 95% CI = 1.11Y1.73, p G .01). For patients with congestive heart failure, mortality was associated with working while sick (OR = 1.39, 95% CI = 1.13Y1.72, p G .01), whereas acute myocardial infarction was associated significantly with weekly burden (hours per week; days in a row) for nurses (OR = 1.33, 95% CI = 1.09Y1.63, p G .01).

Implications of the California Nurse Staffing Mandate for Other States
Linda H. Aiken, Ph.D., et al., Health Services Research, August 2010

The researchers surveyed 22,336 RNs in California and two comparable states, Pennsylvania and New Jersey, with striking results, including: if they matched California limits in medical and surgical units, New Jersey hospitals would have 13.9 percent fewer patient deaths and Pennsylvania 10.6 percent fewer deaths. “Because all hospitalized patients are likely to benefit from improved nurse staffing, not just general surgery patients, the potential number of lives that could be saved by improving nurse staffing in hospitals nationally is likely to be many thousands a year,” according to Linda Aiken, the study’s lead author. California RNs report having significantly more time to spend with patients, and their hospitals are far more likely to have enough RNs on staff to provide quality patient care. Fewer California RNs say their workload caused them to miss changes in patient conditions than New Jersey or Pennsylvania RNs. In California, where hospitals have better compliance with the staffing limits, RNs cite fewer complaints from patients and families and the nurses have more confidence that patients can manage their own care after discharge. California RNs are substantially more likely to stay in their jobs because of the staffing limits, and less likely to report burnout than nurses in New Jersey or Pennsylvania. Two years after implementation of the California staffing law—which mandates minimum staffing levels by hospital unit—“nurse workloads in California were significantly lower” than Pennsylvania and New Jersey. “Most California nurses, bedside nurses as well as managers, believe the ratio legislation achieved its goals of reducing nurse workloads, improving recruitment and retention of nurses, and having a favorable impact on quality of care,” the authors write.

Temporal Trends in Rates of Patient Harm Resulting from Medical Care
Christopher P. Landrigan, M.D., M.P.H., Gareth J. Parry, Ph.D., Catherine B. Bones, M.S.W., Andrew D. Hackbarth, M.Phil., Donald A. Goldmann, M.D., and Paul J. Sharek, M.D., M.P.H., New England Journal of Medicine, November 2010

Among 2,341 admissions, internal reviewers identified 588 harms (25.1 harms per 100 admissions; 95% confidence interval [CI], 23.1 to 27.2). Multivariate analyses of harms identified by internal reviewers showed no significant changes in the overall rate of harms per 1000 patient-days (reduction factor, 0.99 per year; 95% CI, 0.94 to 1.04; P = 0.61) or the rate of preventable harms. There was a reduction in preventable harms identified by external reviewers that did not reach statistical significance (reduction factor, 0.92; 95% CI, 0.85 to 1.00; P = 0.06), with no significant change in the overall rate of harms (reduction factor, 0.98; 95% CI, 0.93 to 1.04; P = 0.47).

The Impact of Medical Errors on 90-Day Costs and Outcomes: An Examination of Surgical Patients
William E. Encinosa and Fred J. Hellinger, Health Services Research, July 2008

A new study published in the journal Health Services Research found that the large difference in calculations for medical error expenses might mean that interventions to increase patient safety — like adding more nursing staff — could be more cost-effective than previously reported. The study found that insurers paid an additional $28,218 (52 percent more) and an additional $19,480 (48 percent more) for surgery patients who experienced acute respiratory failure or post-operative infections, respectively, compared with patients who did not experience either error. Preventing these and other preventable medical errors would reduce loss of life and could reduce healthcare costs by as much as 30 percent, the researchers said. “Many hospitals are struggling to survive financially,” study co-author William Encinosa, senior economist at the Agency for Healthcare Research and Quality, said in a statement. “The point of our paper is that the cost savings from reducing medical errors are much larger than previously thought.” Pointing to previous research that looked at the business case for improving RN staffing ratios, the researchers concluded: “It is quite possible that the post-discharger costs savings achieved by reducing adverse events might just be enough for the hospital to break-even on the investment in nursing.”

Overcrowding and Understaffing in Modern Health-care Systems: Key Determinants in Meticillin-resistant Staphylococcus Aureus Transmission
Archie Clements, et al, Lancet Infectious Disease, July 2008

A new study published in the July issue of the journal Lancet Infectious Disease finds that understaffing of nurses is a key factor in the spread of methicillin-resistant Staphylococcus aureus (MRSA), the most dangerous type of hospital acquired infection. “Overcrowding and understaffing have had a negative effect on patient safety and quality of care, evidenced by the flourishing of health-care-acquired MRSA infections in many countries, despite efforts to control and prevent these infections from occurring. There is an urgent need for a requirement for developing resource allocation strategies that minimize MRSA transmission without compromising the quality and level of patient care,” the researchers concluded. The authors note that common attempts to prevent or contain MRSA and other types of infections such as requirements for regular and repeated hand washing by nurses are compromised when nursing staff are overburdened with too many patients. They also note that hospitals now involve nurses in a “vicious cycle” where a call for nurses to increase their infection control procedures “are seldom accompanied by increases in staffing levels and thus represent an additional work burden on nursing staff” that leads to a greater spread of infections.

Nurse Satisfaction and the Implementation of Minimum Nurse Staffing Regulations
Joanne Spetz, Ph.D, Policy, Politics & Nursing Practice, April 3, 2008

A statewide survey of nurses in California found that nurses perceived a significant improvement in their working conditions and were more satisfied with their jobs in the two years following implementation of the landmark California staffing law in 2004. According to the researchers, “Nurse satisfaction with many aspects of work increased significantly between 2004 and 2006. The largest changes in satisfaction, in percentage terms, were with adequacy of staff (a 12.95 % increase), providing patient education (+7.3%), clerical support (6.9%) and satisfaction with the job overall (5.9%).” The authors concluded: “A large body of research links job satisfaction, heavy workload, job stress, effective management and career development opportunities with turnover rates. It is possible that the improvements in RN satisfaction documented here will facilitate higher quality of care. High nurse turnover has a negative effect on the quality of care delivered to patients. If minimum staffing regulations improve nurse satisfaction, reduce job stress, and relieve workload, nurse turnover may indeed decline, further improving the quality of hospital care.”

Survival From In-Hospital Cardiac Arrest During Nights and Weekends
Mary Ann Peberdy, MD, et al., JAMA, February 20, 2008

A national study on the rate of death from cardiac arrest in hospitals found that the risk of death from cardiac arrest in the hospital is nearly 20 percent higher on the night shift.  The authors highlight understaffing during the night shift as a potential explanation for the death rate.  “Most hospitals decrease their inpatient unit nurse-patient limits at night.  Lower nurse-patient limits have been associated with an increased risk of shock and cardiac arrest,” the authors stated.

Nurse Staffing and Patient, Nurse and Financial Outcomes
Lynn Unruh, PhD, RN, AJN, January 2008

This report provides a comprehensive literature review of more than 21 studies published since 2002 that, according to the author, “underscore the importance of hospitals acknowledging the effect nurse staffing has on patient safety, staff satisfaction, and institutions’ financial performance.”  According to the report, “the evidence clearly shows that adequate staffing and balanced workloads are central to achieving good patient, nurse, and financial outcomes. Efforts to improve care, recruit and retain nurses, and enhance financial performance must address nurse staffing and workload. Indeed, nurses’ workloads should be a prime consideration. If a proposed change would improve care and also reduce excessive (or maintain acceptable) workloads, it should be implemented. If not, it shouldn’t be.”

The Impact of Nurse Staffing on Hospital Costs and Patient Length of Stay: A Systematic Review
Petsunee Thungjaroenkul, RN, MS, Nursing Economics, Vol. 25, 2007

This study provides a comprehensive review of the research on the impact of RN staffing limits on hospital costs and patient length of stay (LOS). It identified 17 studies published between 1990 and 2006 and concluded: “the evidence reflected that significant reductions in cost and LOS may be possible with higher ratios of nursing personnel in hospital settings. Sufficient numbers of RNs may prevent patient adverse events that cause patients to stay longer than necessary. Patient costs were also reduced with greater RN staffing as RNs have higher knowledge and skill levels to provide more effective nursing care as well as reduce patient resource consumption. Hospital administrators are encouraged to use higher ratios of RNs to non-licensed personnel to achieve their objectives of quality patient outcomes and cost containment.”

Newly Licensed RNs’ Characteristics, Work Attitudes, and Intentions to Work
Christine T. Kovner, PhD, RN, et al, AJN, September, 2007

A national study on the work experience and attitudes of newly licensed nurses in America found that the majority of new grads had been given full patient assignments immediately following their orientation, with poor supervision and management, while more than 45 percent reported having recently been given more than 6 patients to care for at one time — a patient load that the researchers said placed their patients at an increased risk of injury or death. More than 55 percent reported that they had to work too fast; 33 percent reported having little time to get things done and nearly a third of new grads reported they had too many patients to get their job done well, Not surprisingly, as a result of these conditions, more than 37% of the new nurses say they plan to leave their current job in the next two years, and more than 41% say they, if free to do so, would take another job immediately. The authors conclude: “The proportion of newly licensed RNs who expressed negative attitudes on individual survey items raises the concern that employers will not be able to retain them in the acute care settings where they start out.”

Staffing Level: a Determinant of Late-Onset Ventilator-Associated Pneumonia
Stephanie Hugonnet, et al, Critical Care, July 19, 2007

Understaffing of registered nurses in hospital intensive care units increases the risk of serious infections for patients; specifically pneumonia, a preventable and potential deadly complication that can add thousands of dollars to the cost of care for hospital patients. This type of pneumonia is a leading cause of as many as 2,000 patient deaths in Mass. hospitals, costing as much as $400 million annually.

Nurse Working Conditions and Patient Safety Outcomes
Patricia W. Stone, Ph.D., et al., Medical Care, 45(6): 571-578, June. 2007

A review of outcomes data for more than 15,000 patients in 51 U.S. hospital ICUs showed that those with higher nurse staffing levels had a lower incidence of infections, such as central line associated bloodstream infections (CLSBI), a common cause of mortality in intensive care settings. The study found that patients cared for in hospitals with higher staffing levels were 68 percent less likely to acquire an infection. Other measures such as ventilator-associated pneumonia and skin ulcers were also reduced in units with high staffing levels. Patients were also less likely to die within 30 days in these higher-staffed units. Increasing RN staffing could reduce costs and improve patient care by reducing unnecessary deaths and reducing days in the hospital.

Hospital Workload and Adverse Events
Joel S. Weisman, Ph.D., et al, Medical Care, 45(5): 448-454, May. 2007

A study conducted by researchers at Brigham & Women’s Hospital and Massachusetts General Hospital found that overcrowded and understaffed hospitals that are pushing too hard to streamline and cut costs are putting their patients at risk for medication errors, nerve injuries, infections and other preventable mistakes, A 10% increase in the number of patients assigned to a nurse leads to a 28% increase in adverse events such as infections, medication errors, and other injuries.

Nurse Staffing and Quality of Patient Care
Robert L. Kane, MD., et al, Evidence Report/Technology Assessment for Agency for Healthcare Research and Quality, AHRQ Publication No. 07-E005, May. 2007

A comprehensive analysis of all the scientific evidence linking RN staffing to patient care outcomes found consistent evidence that an increase in RN-to-patient ratios was associated with a reduction in hospital-related mortality, failure to rescue, and other nurse sensitive outcomes, as well as reduced length of stay. Every additional patient assigned to an RN is associated with a 7% increase in the risk of hospital-acquired pneumonia, a 53% increase in respiratory failure, and a 17% increase in medical complications.

Quality of Care for the Treatment of Acute Medical Conditions in U.S. Hospitals
Bruce E. Landon, MD, MBA., et al, Archives of Internal Medicine, 166: 2511-2517, Dec 11/25. 2006

A national study of the quality of care for patients hospitalized for heart attacks, congestive heart failure and pneumonia found that patients are more likely to receive high quality care in hospitals with higher registered nurse staffing ratios.

Impact of Hospital Nursing Care on 30-day Mortality for Acute Medical Patients
Ann E. Tourangeau, Ph.D., et al., Blackwell Publishing: 32-44, Aug. 2006

A study of 46,000 patients in 76 hospitals found the adequacy of nurse staffing and proportion of registered nurses is inversely related to the death rate of acute medical patients within 30 days of hospital admission. The study’s authors recommend that “if hospitals have goals of minimizing unnecessary patient death for their acute medical patient population, they should maximize the proportion of Registered Nurses in providing direct care.”

HeathGrades Quality Study: Third Annual Patient Safety in American Hospital Study
HealthGrades, Inc: April 2006

80,000 Medicare patients each year died between 2002 – 2004 in our nation’s hospitals from preventable medical errors, with 63% of those deaths attributable to failure to rescue by a registered nurse or physician. Massachusetts ranked 22nd in patient safety, with no improvement since the previous year’s study.

Nurse Staffing in Hospitals: Is There a Business Case For Quality?
Jack Needleman, Ph.D., Peter Buerhaus, Ph.D., R.N., et al., Health Affairs, 25(1): 204-211, Jan.-Feb. 2006

Increasing the proportion of RNs without increasing total nursing hours per day could reduce costs and improve patient care by reducing unnecessary deaths and reducing days in the hospital.

Longitudinal Analysis of Nurse Staffing and Patient Outcomes – More About Failure to Rescue
Jean Seago, Ph.D., et al., JONA, 36(1): 13-21, Jan. 2006

Increasing RN staffing increased patient satisfaction with pain management and physical care; while “having more non-RN” care “is related to decreased ability to rescue patients from medication errors.”

Correlation Between Annual Volume of Cystectomy, Professional Staffing, and Outcomes – A Statewide, Population-Based Study
Linda Elting, Ph.D., et al., Cancer, 104(5): 975-984, Sept. 2005

Patients undergoing common types of cancer surgery are safer in hospitals with higher RN-to-patient ratios. High RN-to-patient ratios were found to reduce the mortality rate by greater than 50% and smaller community hospitals that implement high RN ratios can provide a level of safety and quality of care for cancer patients on a par with much larger urban medical centers that specialize in performing similar types of surgery.

Improving Nurse-to-Patient Staffing Ratios as a Cost-Effective Safety Intervention
Michael Rothberg, et. al, Medical Care, 43(8): 785-791, Aug. 2005

Improving RN-to-patient limits could save thousands of lives each year and is more cost effective than clot-busting medications for heart attacks and strokes, and cancer screenings.

Hospital Speedups and the Fiction of the Nursing Shortage
Gordon Lafer, Labor Studies Journal, 30(1): 27-45, Spring 2005

“There is no shortage of nurses in the United States. The number of licensed registered nurses in the country who are choosing not to work in the hospital industry due to stagnant wages and deteriorating working conditions is larger than the entire size of the imagined ‘shortage.’ Thus, there is no shortage of qualified personnel — there is simply a shortage of nurses willing to work under the current conditions created by hospital managers.”

Nurses’ Working Conditions: Implications for Infectious Disease
Patricia W. Stone, et al., Emerging Infectious Disease, 10(11): 1984-1989, Nov. 2004

Improving nurse staffing and working conditions “are likely to improve the quality of health care by decreasing incidence of many infectious diseases, and assisting in retaining qualified nurses.”

The Working Hours of Hospital Staff Nurses and Patient Safety
Ann E. Rogers, et al., Health Affairs, 23(4): 202-212, July/Aug. 2004

Nurses working mandatory overtime are three times more likely to make a medical error. “Overtime, especially that associated with 12-hour shifts, should be eliminated.”

Association Between Evening Admissions and Higher Mortality Rates in the Pediatric Intensive Care Unit
Yeseli Arias, M.D., et. al, Pediatrics, 113(6): e530-e534, June 2004

Children admitted to pediatric intensive care units at night are more likely to die in the first 48 hours of care; authors point to fatigue and lighter nurse staffing levels as contributing factors.

Consumer Perspectives: The Effect of Current Nurse Staffing Levels on Patient Care
National Consumers League Report, May 2004

National survey of recent patients in hospitals found that 45% believed their safety was compromised by understaffing of nurses; 12% believed their safety was extremely compromised. 78% of respondents support safe staffing legislation.

Nurse Staffing Levels and Quality of Care in Hospitals
Mark W. Stanton, M.A., AHRQ Research in Action, 14; March 2004

Poor hospital registered nurse staffing is associated with higher rates of urinary tract infections, post-operative infections, pneumonia, pressure ulcers and increased lengths of stay, while better nurse staffing is linked to improved patient outcomes.

Nurse Burnout and Patient Satisfaction
Doris C. Vahey, Ph.D., et al., Medical Care, 42(2): II-57-II-66, Feb. 2004

Improvements in nurse staffing in hospitals “simultaneously reduces nurses’ high burnout and risk of turnover and increases patients’ satisfaction with their care.”

Is More Better? The Relationship Between Nurse Staffing and the Quality of Nursing Care in Hospitals
Julie Sochalski, Medical Care, 42(2): II-67-II-73, Feb 2004

Survey of 8,000 RNs in Pennsylvania hospitals found workload and understaffing contributed to medical errors and patient falls and to a number of important nursing tasks left undone at the end of every shift.

Nurse Staffing and Mortality for Medicare Patients with Acute Myocardial Infarction
Sharina D. Peterson, Ph.D., et al., Medical Care, 42(1): 4-12, Jan. 2004

“Medicare patients with AMI (heart attack) who were treated in higher RN staffing environments had a significant in-hospital mortality advantage.” Conversely, patients are more likely to die in hospitals with high LPN staffing environments. “The mortality difference we observed are related to differences in hospital staffing patterns and may derive from substitution of personnel with less training or experience.”

The Shocking Cost of Turnover in Health Care
J. Deane Waldman, M.D., M.B.A., et al., Health Care Management Review, 29(1): 2-7, Jan. – March 2004

The cost for advertising, training and loss in productivity associated with recruiting new nurses to a facility is $37,000 per nurse at minimum and can add as much as 5% to a hospital’s annual budget. Improving nurses’ staffing conditions is a primary strategy for hospitals that can generate significant cost savings.

Keeping Patients Safe: Transforming the Work Environment of Nurses (Executive Summary) Institute of Medicine, National Academy of Sciences, Nov. 2003

Following up on the 1999 report on patient safety, To Err is Human, the Institute for Medicine calls for improved nurse-to-patient limits, limits on mandatory overtime, and nurse involvement on every level to protect patients.

Licensed Nurse Staffing and Adverse Events in Hospitals
Lynn Unruh, Ph.D., Medical Care, 41(1): 142-152, 2003

Hospitals with better licensed nurse staffing had a significantly lower incidence of adverse patient events, including bed sores, patient falls and pneumonia.

Nurse Staffing, Quality, and Hospital Financial Performance
Barbara Mark, Ph.D., et al., Journal of Health Care Finance, 29(4): 54-76, Summer 2003

Increased staffing of registered nurses does not significantly decrease a hospital’s profit margin, even though it boosts the hospital’s operating costs.

The Effects of Nurse Staffing on Adverse Events, Morbidity, Mortality, and Medical Costs
Sung Hyun Cho, Ph.D., et al., Nursing Research, 52(2): 71-79, March/April 2003

Increasing nurse staffing by just one hour per patient day resulted in a 10% reduction in the incidence of hospital-acquired pneumonia. The cost of treating hospital acquired pneumonia is $28,000 per patient.

Patient-to-Nurse Staffing Ratios: Perspectives from Hospital Nurses
Peter D. Hart Research Corp., A Research Study for AFT Health Care, April 2003

Three in five nurses say they are responsible for too many patients at one time and the problem is harming care. 82% of nurses support legislation setting limits on nurses’ patient assignments.

Hospital Nurse Staffing and Patient Mortality, Nurse Burnout, and Job Dissatisfaction
Linda Aiken Ph.D., R.N., Journal of the American Medical Association, October 22, 2002

For each additional patient over four assigned to an RN, the risk of death increases by 7% for all patients. Patients in hospitals with a 1:8 nurse-to-patient ratio have a 31% greater risk of dying than patients in hospitals with 1:4 nurse-to-patient limits. Legislation to regulate RN-to-patient limits is a credible means of protecting patients and to ending the nursing shortage.

Strengthening Hospital Nursing
Jack Needleman, Ph.D., et al., Health Affairs, 21(5): 123-132, Sept./Oct. 2002

“The implications of doing nothing to improve nurse staffing levels in many low-staffed hospitals are that a large number of patients will suffer avoidable adverse outcomes and hospitals and patients will continue to incur higher costs than are necessary.”

Nurse Staffing and Healthcare-associated Infections
Marguerite Jackson, Ph.D., R.N., et al., JONA, 32(6): 314-322, June 2002

“There is compelling evidence of a relationship between nurse staffing and adverse patient outcomes,” including serious bloodstream infections in hospital patients.

Nurse-Staffing Levels and Quality of Care in Hospitals
Jack Needleman, Ph.D., et al., The New England Journal of Medicine, 346(22): 1715-1722, May 30, 2002

A higher proportion of RNs in the staff mix and a greater number of nursing hours per day are associated with better patient outcomes.

Health Policy Report – Nursing in the Crossfire
Robert Stimson, M.D., New England Journal of Medicine, 346(22): 1757-1766, May 30, 2002

Provides a review of the research underlying the current crisis in nursing with recommendations for policy, including legislation to regulate RN limits and to recruit nurses into the profession.

Health Care at the Crossroads: Strategies for Addressing the Evolving Nursing Crisis
Joint Commission on Accreditation of Healthcare Organizations (JCAHO), 2002

JCAHO found that low staffing levels were a contributing factor in 24% of patient safety errors resulting in injuries or death since 1996. Recommends transforming the nursing workplace and giving hospitals an incentive to invest in high quality nursing care.

Intensive Care Unit Nurse Staffing and the Risk of Complications After Abdominal Aortic Surgery
Peter J. Pronovost, M.D., Ph.D., et al., Effective Clinical Practice, 4(25): 199-206, Sept./Oct. 2001

Patients treated in hospitals with fewer ICU nurses were more likely to have medical complications, respiratory failure or need a breathing tube inserted. The study also found the ICUs with fewer RNs incurred a 14% increase in costs.

Nurses’ Reports on Hospital Care in Five Countries
Linda H. Aiken, Ph.D., R.N., et al., Health Affairs, 20(3): 43-53, May/June 2001

Study finds widespread job dissatisfaction among hospital nurses in the US due to understaffing and poor working conditions. Half of US nurses report the quality of care at their hospital has deteriorated in the last year; one in five nurses overall and one in three nurses under 30 plan on leaving bedside nursing.

The Nursing Crisis in Massachusetts
Report of the Legislative Special Commission on Nursing and Nursing Practice, May 2001

“It is the unanimous consensus of licensed nurses, health care personnel and administrators that the shortage of nursing care in the Commonwealth is endangering the quality of care that our nurses can provide to the patient.” The Commission’s top two recommendations to solve the crisis include legislation to ban mandatory overtime and to set RN-to-patient limits.

ICU Nurse-to-Patient Ratio is Associated with Complications and Resource Use After Esophagectomy
Peter J. Pronovost, M.D., Ph.D., et al., Intensive Care Medicine, 26: 1857-1862, 2000

A nurse caring for more than two ICU patients at night increases the risk of several post-operative pulmonary and infectious complications and was associated with increased resource use. The study advocates a limit of one RN to no more than two patients.

Organization and Outcomes of Inpatient AIDS Care
Linda H. Aiken, Ph.D., R.N., et al., LDI Issue Brief, 8(1): Sept. 1999

Higher nurse-to-patient ratios are strongly associated with a lower mortality for patients with AIDS in hospitals.

Nurse Staffing and Patient Outcomes
Mary A. Blegen, Ph.D., R.N., et al., Nursing Research, 47(1): 43-50, Jan./Feb.1998

Inpatient units with a higher proportion of RN care had fewer adverse patient outcomes, including fewer medication errors, bedsores and patient complaints. Conversely, when more care was delivered by non-RN team members, rates of bedsores, complaints and patient deaths increased.

Downsizing the Hospital Nurse Workforce
Linda H. Aiken, Ph.D., R.N., et al., Health Affairs, 15(4): 88-92, Winter 1996

Hospitals cut nurse staffing levels in the 90s by 7.3% nationally, while all other categories of hospital personnel increased, including a 46% increase in non-nurse administrative personnel and a 50% increase in other direct care staff. Massachusetts cut its RN staffing by 27%, highest in the nation.