Patient outcomes and toll savings associated with infirmary prophylactic nurse staffing legislation: an observational study

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  1. http://orcid.org/0000-0002-5834-1954Karen B Lasaterone,2,
  2. http://orcid.org/0000-0001-8004-3630Linda H Aikenone,two,
  3. Douglas Sloanei,
  4. Rachel French1,ii,
  5. Brendan Martinthree,
  6. Maryann Alexander3,
  7. http://orcid.org/0000-0002-1263-0697Matthew D McHugh1,2
  1. 1 Middle for Wellness Outcomes and Policy Inquiry, School of Nursing, Academy of Pennsylvania, Philadelphia, Pennsylvania, Us
  2. 2 Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, Pennsylvania, United states
  3. 3 National Council of Land Boards of Nursing, Chicago, Illinois, USA
  1. Correspondence to Karen B Lasater; karenbl{at}nursing.upenn.edu

Abstract

Objective To evaluate variation in Illinois hospital nurse staffing ratios and to determine whether higher nurse workloads are associated with bloodshed and length of stay for patients, and toll outcomes for hospitals.

Design Cross-sectional analysis of multiple data sources including a 2020 survey of nurses linked to patient outcomes data.

Setting: 87 acute care hospitals in Illinois.

Participants 210 493 Medicare patients, 65 years and older, who were hospitalised in a report infirmary. 1391 registered nurses employed in direct patient care on a medical–surgical unit in a study infirmary.

Main effect measures Primary outcomes were 30-twenty-four hours mortality and length of stay. Deaths avoided and cost savings to hospitals were predicted based on results from regression estimates if hospitals were to have staffed at a iv:1 ratio during the report period. Cost savings were computed from reductions in lengths of stay using cost-to-charge ratios.

Results Patient-to-nurse staffing ratios on medical-surgical units ranged from four.2 to 7.6 (mean=five.4; SD=0.7). After adjusting for hospital and patient characteristics, the odds of 30-twenty-four hour period mortality for each patient increased by sixteen% for each additional patient in the boilerplate nurse'south workload (95% CI one.04 to one.28; p=0.006). The odds of staying in the hospital a 24-hour interval longer at all intervals increased by 5% for each additional patient in the nurse's workload (95% CI 1.00 to one.09, p=0.041). If report hospitals staffed at a iv:1 ratio during the 1-year study period, more than 1595 deaths would have been avoided and hospitals would have collectively saved over $117 million.

Conclusions Patient-to-nurse staffing ratios vary considerably across Illinois hospitals. If nurses in Illinois hospital medical–surgical units cared for no more than four patients each, thousands of deaths could be avoided, and patients would experience shorter lengths of stay, resulting in cost-savings for hospitals.

  • health services administration & direction
  • health & safety
  • health policy
  • system of wellness services
  • quality in health intendance

Data availability argument

No data are bachelor.

http://creativecommons.org/licenses/by-nc/4.0/

This is an open access article distributed in accordance with the Artistic Commons Attribution Non Commercial (CC By-NC four.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, whatever changes made indicated, and the use is non-commercial. Run into: http://creativecommons.org/licenses/by-nc/4.0/.

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  • health services administration & management
  • health & safety
  • wellness policy
  • organization of health services
  • quality in health care

Strengths and limitations of this study

  • Study blueprint, staffing and outcome measures are similar to previously published studies evaluating the link between nurse staffing and patient outcomes.

  • Staffing measures collected as prepolicy implementation baseline data to quantify the scope of the variation in staffing within Illinois state, and the impact of staffing variation on the public's health.

  • Patient-to-nurse staffing measures are derived straight from staff nurses on medical and surgical units.

  • Patient outcomes are risk-adapted 30-day mortality and hospital length of stay.

  • The cross-sectional report pattern precludes causal statements near the relationship of nurse staffing and patient outcomes.

Introduction

Despite substantial evidence that high registered nurse (RN) workloads are related to patient mortality—amid other adverse patient outcomes1–4—no US states, except for California,5 take implemented minimum hospital nurse staffing requirements. While many Usa states accept pursued legislation to regulate hospital nurse staffing levels, support for such regulation is dampened for iii primary reasons: (one) lack of prepolicy data documenting significant variation of infirmary nurse staffing ratios across the state debating staffing regulation, (2) lack of local, timely evidence demonstrating variation in nurse staffing adversely affects patient outcomes and (3) an underdeveloped business concern example to justify the financial investments required to staff greater numbers of nurses at the bedside.

In this study, we accost each of these three concerns using 2020 data from a large sample of 87 hospitals in Illinois where legislation to mandate patient-to-nurse staffing ratios is actively being debated (HB 2604 Safe Patient Limits Deed).six We projection the number of deaths and hospital days that could be avoided, if Illinois hospitals staffed medical–surgical nurses at the 4:1 patient per nurse ratio proposed in the legislation. Because reductions in patient length of stays accept economic implications for hospitals, we estimate the potential cost savings to hospitals through reduced lengths of stay if hospitals moved to the 4:1 staffing ratio.

This is the first study to written report local and timely evidence about staffing variation in a big sample of hospitals beyond Illinois, and the consequences of staffing variation for patient outcomes and costs of care to straight inform public policy efforts actively nether consideration. The master objectives of this study are to evaluate variation in Illinois hospital nurse staffing ratios and to determine whether higher nurse workloads are associated with mortality and length of stay for patients, and cost outcomes for hospitals.

Background

Nurses are the around-the-clock surveillance system of hospitals; closely monitoring changes in patients' clinical condition and administering treatments and care as appropriate. When nurses care for fewer patients at time, they are able to spend more time at each patient'south bedside, and equally a consequence, patients are less probable to experience an adverse effect such as a hospital-acquired infection,vii poor glycaemic control,8 readmission9 and even death.10–fourteen The clinical benefits of nurse staffing have primarily been studied in adult medical and surgical populations, but have likewise been observed in special populations including babies in neonatal intensive care units15 and children;16 and may too be key to reducing racial disparities in outcomes.nine 17–19 The benefits of amend nurse staff extend to nurses every bit well; with nurses in ameliorate-staffed hospitals reporting less exhaustion, less job dissatisfaction and being less likely to intend to leave their employer.10 xx

An emerging trunk of enquiry evidence articulates the human and economical consequences of agin patient outcomes that effect from infirmary nurse understaffing. For example, an analysis of hospital nurse staffing amongst New York hospitals found that if hospitals staffed medical–surgical units with iv patients per nurse, as opposed to the average hospital ratio of half dozen.3 patients per nurse, then thousands of deaths could have been avoided and many hundreds of millions of dollars saved through shorter lengths of stay and avoided readmissions.21 The same study22 showed that improving nurse staffing in New York hospitals would take reduced deaths among sepsis patients more than a policy passed earlier that mandated adherence to a standardised set of services for sepsis patients. A report of adult medical patients showed that patients in hospitals with meliorate nurse resources had better outcomes including less mortality, fewer readmissions and shorter lengths of stay—at no difference in cost, when compared with similar patients in hospitals with poorer resources.23 These study findings have been corroborated in surgical patients;24 25 and discover that improving nurse staffing would avoid adverse outcomes with sizeable price savings to hospitals.26

Despite the social and economic instance for improving hospital nurse staffing, California remains the only US state to accept implemented required staffing standards. Passed in 1999 and implemented in 2004, the California legislation resulted in improved staffing, with the greatest improvements observed among condom-net hospitals.27 Compared with other states which did not implement condom staffing requirements, patients in California hospitals experienced lower bloodshed and failure-to-rescue rates.v 28 The California experience serves equally an example of a successfully implemented and sustained state-wide policy mandate for prophylactic hospital staffing and patient care.

Information and methods

Pattern

This observational study of hospitals and patients uses multiple linked data sources including Medicare patient claims data, American Hospital Association (AHA) data of hospital characteristics and a survey of RNs to provide information on hospital nurse staffing ratios on medical and surgical units.

Patient sample

The patient sample includes persons insured by Medicare who were 65 years and older (the qualifying age for Medicare—the Us federal regime health insurance plan) and who were admitted to an astute care hospital in Illinois in 2018. Data on Medicare patients were obtained from the Centers for Medicare and Medicaid Services (CMS) MEDPAR files. Patients admitted for psychiatric reasons and drug/alcohol employ were excluded, equally were patients with lengths of stay greater than sixty days. Each unique patient was assigned an index hospitalisation, created past selecting the beginning access during the study period. The analytic sample included only these index hospitalisations, which deemed for roughly half of all the Medicare hospitalisations in Illinois during the study flow.

Hospital sample

Short-term acute care and critical access hospitals that had medical and surgical straight care nurses who responded to the survey of nurses were included. The survey of nurses was sent via electronic mail to all actively licensed RNs in the state of Illinois (n=168 001). Data drove ran from 16 December 2019 to 24 February 2020. Nurse responses were anonymous, but nurses were asked to report the proper name of their employer, thus allowing responses from nurses working in the same hospitals to be aggregated together to create hospital-level measures of patient-to-nurse staffing ratios. Our data collection method relies on nurses every bit key informants of their hospital.29 Thus, while we directly survey nurses, our involvement is in hospital-level organisational measures, in this instance, patient-to-nurse staffing ratios.

The nurse response charge per unit was 18% of the 168 001 RNs surveyed, which is predictable considering endemic difficulties with survey response rates30 and the fact that our sampling frame consisted of 100% of licensed nurses in the country, but a fraction of whom are employed in hospitals, which was the focus of our study. A similar survey conducted in other states yielded comparable response rates. In the broader multistate study, the survey implemented a double-sampling arroyo to evaluate for potential non-response bias. The results demonstrated that nurse reports of patient-to-nurse staffing ratios were no different among nurses who responded to the main survey and those that responded to the non-respondent survey.29 Thus despite an eighteen% response rate, prove suggests that even if non-response bias were present, it probable does not affect the validity of the resultant staffing estimates.

Because this is a written report of hospitals and the patients in them, the nurse survey response charge per unit is of somewhat lesser importance than the caste to which the survey achieved adequate representation of hospitals (via a loftier hospital response charge per unit) and the patients in them. We excluded hospitals that were long-term rehabilitation hospitals, psychiatric facilities or free-standing children's hospitals. Based on the remaining acute intendance hospitals, our analytic sample of 87 hospitals represented 86.5% of Medicare index admissions in the state and roughly ii-third of the short-term astute care hospitals in Illinois. We accept less representation of critical access hospitals since we were not able to obtain data from enough nurses in those small facilities to reliably estimate staffing ratios.

Patient-to-nurse staffing

Surveyed nurses were asked to report whether they were working in straight patient intendance or indirect care positions (eg, direction); which blazon of unit they worked on and how many patients they were assigned to intendance for on their most contempo shift. But data from direct intendance RNs who reported working their almost recent shift on a medical or surgical unit were used to create our measure of staffing. Responses were then aggregated to create a hospital-level measure of medical–surgical patient-to-nurse staffing. The survey besides asked nurses to report how many patients they could safely treat in their job setting.

Patient outcomes

Patient outcome measures included 30-mean solar day mortality and infirmary length of stay. thirty-24-hour interval mortality was divers as a death occurring thirty-days from date of access and included deaths that occurred outside of the hospital. Infirmary length of stay was divers as total number of days in the hospital during the index admission.

Price outcomes

Cost savings were estimated using Medicare-specific toll-to-charge ratios using patient-level charge data from the MEDPAR files. Toll savings from reductions in length of stay were computed past first estimating the predicted reduction in patient days if hospitals staffed at the iv:1 ratio, then applying the reduction to total charges and then converting to costs using the hospital-level Medicare-specific cost-to-charge ratios from CMS Impact Files.

Hazard-adjustment

Hospital risk-aligning variables included infirmary size, defined by number of beds, from the AHA Annual Survey. Patient covariates included patient age, sex activity, Elixhauser comorbidities,31 dummy variables for diagnostic-related groups—and in models estimating effects of staffing on length of stay, patient discharge disposition status.

Statistical analysis

Descriptive statistics were used to evidence medical–surgical nurse staffing ratios, and the numbers of patients and nurse survey respondents in the 87 written report hospitals. Patient characteristics (eg, historic period, sexual practice, transfer condition, comorbidities) as well as percentage of patients who died within xxx-days of admission and boilerplate (and SD) length of stay are reported. Nosotros also show percentages of nurses who reported that the number of patients they cared for during their last shift exceeded the number of patients they felt they could safely care for. Prior to accounting for confounding factors, nosotros testify variation in patient mortality rates and lengths of stay among hospitals with different staffing levels (ie,<five, v≤six, ≥6 patients per nurse).

Multilevel random-effects logistic regression models and zero-truncated negative binomial regression models were used to estimate the association between nurse staffing with 30-day bloodshed and length of stay, respectively. These associations were estimated before and after accounting for potentially confounding hospital and patient characteristics. Using adjusted estimates from our regression models, nosotros estimated how many deaths could have been avoided and how much money could have been saved (from shorter lengths of stay) were hospitals to staff medical–surgical nurses at the levels proposed in the legislation (4:1 patients per nurse). STATA was used to perform the analyses. This report received IRB approving from the Academy of Pennsylvania (Protocol #834307).

Patient and public involvement

No patient involved.

Results

Our analytic sample included 210 493 Medicare beneficiaries in 87 Illinois hospitals (table one). Staffing estimates were derived from an average of 16 direct care medical–surgical nurse respondents per infirmary, with as many as 68 nurse respondents in larger hospitals. Medical–surgical staffing ratios ranged from iv.ii to 7.6 patients per nurse, with the lower bound simply above the four patients per nurse proposed in the legislation. The average staffing ratio in Illinois hospitals was 5.4 and somewhat higher (5.6) among smaller hospitals than larger hospitals (five.three).

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Table ane

Hospital size, numbers of patients and nurse respondents and patient-to-nurse staffing ratios amongst 87 Illinois study hospitals

Amid the study patients, 5.8% died within 30-days of admission and the average length of stay was iv.1 days, with a SD of iii.seven days (online supplemental table 1). Twoscore percent of the patients were 80 years of age or older, and 56% were female person. The nearly common comorbidities included hypertension, fluid and electrolyte disorders, chronic pulmonary disease and renal failure. Nurses reported rubber concerns related to the number of patients they cared for during their last shift (table two). Half of nurses (51.2%) reported that their patient assignment during their last shift exceeded the number they assessed they could safely care for. Two-thirds of nurses (67.0%) who were assigned 6 or more patients assessed that workload was dangerous. Nigh nurses (82.7%) who were assigned four or fewer patients assessed that patient assignment constituted a safe workload.

Supplemental material

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Table 2

Percent of nurses reporting that the number of patients assigned to them during the final shift exceeded the number they could safely care for

Prior to adjusting for confounding variables of the hospitals and patients, we found that patient mortality and lengths of stay in hospitals varied with unlike nurse staffing ratios (table 3). The average 30-24-hour interval bloodshed rate amid hospitals with an boilerplate staffing ratio of <5 patients per nurse was lower (5.6%) compared with mortality among hospitals where nurses cared for betwixt v≤6 patients (6.1%) and ≥6 patients (6.1%). Lengths of stay were shorter in hospitals where nurses cared for fewer patients at a time (four.0 days in hospitals with <5 patients per nurse, vs 4.1 days in hospitals with 5≤6 patients per nurse, vs 4.5 days in hospitals with ≥6 patients per nurse).

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Table 3

Boilerplate mortality and lengths of stay for patients in hospitals with different patient-to-nurse staffing ratios

Table 4 presents the upshot of nurse staffing on mortality and length of stay. After adjusting for hospital and patient characteristics, the odds of xxx-day mortality for each patient increased by a factor of i.16 (or xvi%) for each additional patient added to the average nurse'south workload (OR 1.16, 95% CI 1.04 to 1.28; p 0.006). The odds of staying in the infirmary a day longer at all intervals increased by a factor of 1.05 (or five%) for each boosted patient in the nurse's workload (IRR ane.05, 95% CI 1.00 to one.09, p 0.041).

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Table iv

Event of medical–surgical patient-to-nurse staffing on patient outcomes

Using these results from the adapted regression models, nosotros estimated the number of deaths that would accept been avoided if hospitals staffed at the four patients per nurse recommendation in the proposed policy (as opposed to the observed ratio which was greater than iv patients per nurse in all hospitals and most eight patients per nurse in some of them). Roughly 1595 deaths could have been avoided among Medicare beneficiaries in the written report hospitals during the ane-yr study menstruum. Improving staffing ratios to the iv:1 ratio was projected to reduce patient lengths of stay by over 40 000 days. These reductions in lengths of stay would collectively save Illinois hospitals over $117 million per yr (table v).

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Table 5

Deaths avoided and cost savings from shorter lengths of stay with 4:i staffing ratios

Discussion

Studying a big sample of 87 acute care hospitals in Illinois, nosotros establish considerable variation in medical–surgical nurse staffing ratios, ranging from 4.ii to vii.half-dozen patients per nurse. The average hospital staffing across the country (outside intensive care settings) was 5.four patients per nurse, which is nearly 1.5 patients above the recommended staffing levels proposed in the HB 2604 Safety Patient Limits Act.6 Half (51.2%) of nurses reported their patient assignment during their final shift was dangerous; and among nurses assigned four of fewer patients, only 17.3% found that staffing ratio to be dangerous.

Staffing conditions were associated with adverse health outcomes for Medicare patients, including mortality and longer lengths of stay. Each additional patient in a nurse'south workload increased the odds of patient decease by xvi%. If the study hospitals had been staffing medical–surgical nurses at the proposed ratio during the 1-year study catamenia, we projected that 1595 deaths would have been avoided just amidst Medicare patients. Had our study considered patients of all ages who would benefit from improved nurse staffing, we anticipate considerably more deaths would accept been avoided.

The odds of Medicare patients staying in the infirmary a day longer increased by 5% for each additional patient in the nurse'south workload. Hospitals would have collectively saved over $117 million annually from length of stay reductions just amidst Medicare patients—toll savings which could exist reinvested into financing safer nurse staffing ratios. These findings are consequent with other inquiry conducted in New York hospitals32 and internationally33 34 which testify that patients in hospitals with better nurse staffing take shorter lengths of stay as well as fewer readmissions, both of which translate to avoided costs. Studies conducted in Queensland Australia and Chile demonstrate that the magnitude of the cost savings associated with better nurse staffing were in excess of the costs of hiring more nurses;33 34 a illustration of the value proposition for increasing nurse staffing.

In the current written report, estimates of avoidable deaths and cost savings are conservative. Our analysis used roughly one-half of the annual Medicare hospitalisations in Illinois state since we restricted the sample to index hospitalisations. Other studies show that patients of all ages benefit from improved hospital nurse staffing.xvi 35 Thus, if the staffing policy were to be enacted, the human and economic benefits would likely be much greater. Additionally, our cost savings assay is conservative considering it does non account for the savings that may exist realised from reductions in nurse burnout and turnover that result from chronic understaffing. In a previously published paper on nurse staffing in Illinois hospitals, we showed that hospital understaffing is associated with poor nurse outcomes including burnout, chore dissatisfaction and intent to leave.20 36 Nurse burnout has been linked with worse patient outcomes including bloodshed and longer lengths of stay37 and intent to get out is associated with turnover.38–40 Turnover of nurses is cost consequential for hospitals, with estimates of replacing a unmarried bedside nurse ranging from $20 56141 to $88 000.42 Although evidence demonstrates that price savings tin can exist achieved—via shorter lengths of stay and reduced readmissions—from staffing more nurses at the bedside, time to come research could expand the scope of the economical consequences of improving nurse staffing in terms of other patient and nurse outcomes with their associated cost savings.

Strengths and limitations

This written report uses hospital medical–surgical nurse staffing data collected in 2020 to inform current staffing policy debates in Illinois. Rarely is timely, rigorous and objective evidence, analysed by an contained squad of researchers, bachelor to inform policy in this way. Reporting lags in claims data meant that the near recent available data on patients were from 2018. Although the hospital staffing and patient information do not coincide, hospital nurse staffing has inverse little in the concluding decade.43 Thus, the staffing estimates obtained in 2020 probable resemble those in 2018. While our written report included near large and medium size hospitals in Illinois, which account for most hospitalised patients in the state, smaller hospitals including disquisitional access hospitals are underrepresented in the written report. The cantankerous-sectional study pattern precludes causal statements well-nigh the relationship between nursing staffing and patient outcomes.

Implications for policy controlling

A recent United states Harris Poll44 suggests that 90% of the U.s. public favour requiring hospitals to run across minimum safe nurse staffing standards. Our report finds uneven nurse staffing among Illinois hospitals which poses unfavourable consequences for patients and hospitals. If Illinois enacted the Safe Patient Limits Human activity, our analysis suggests thousands of deaths per yr could exist avoided. Additionally, hospitals could relieve substantially through reductions in patients' lengths of stay associated with improving nurse staffing. These savings could exist reinvested into the costs of employing boosted nurses.

Enacting the Prophylactic Patient Limits Human action would likely create opportunities for more nurses to enter the workforce, raising questions about where these nurses would be drawn from. There is currently no widespread shortage of actively licensed RNs. Nurse graduations are at an all-time high, with enough nurses inbound the workforce annually to more than replace retirements.45 California, the merely land to enact nurse staffing ratio mandates similar to what is existence proposed in Illinois, has successfully implemented the ratios despite have a lower nurse-to-population ratio compared with Illinois (11.three RNs per 1000 population in California; 16.seven RNs per 1000 population in Illinois).46 Finally, the Nurse Licensure Compact, which is country legislation to allow nurses to concur a multistate US license is currently under consideration in Illinois.47 Passing such legislation would enable nurses licensed in any of the 34 states currently in the Compact to practice in any other Compact land, without the brunt of having to obtain an additional license. Such legislation permits greater mobility of nurses to do across state lines. Thus, trends in the nursing workforce and the opportunity for Illinois to join the Nurse Licensure Compact suggest it is unlikely that passing mandated prophylactic nurse staffing legislation would result in nursing shortages that would negatively affect access to intendance or care quality.

Conclusions

Nurse staffing on medical and surgical units in Illinois hospitals averaged 5.4 patients per nurse and ranged from as few equally four.2 patients per nurse to as many every bit to 7.6. These estimates propose that few Illinois hospitals are currently meeting the minimum staffing levels which would be required by the Condom Patient Limits Human action currently nether consideration. Nosotros establish that each additional patient in a nurses' workload was associated with 16% higher odds of death and longer lengths of stay. If Illinois hospitals staffed medical and surgical units at the ratio proposed in the legislation, nosotros project thousands of deaths could exist avoided each year and patients would experience shorter lengths of stay resulting in hundreds of millions of dollars in cost-savings for hospitals.

Information availability statement

No data are available.

Ideals statements

Patient consent for publication

Ethics blessing

The study was canonical by the University of Pennsylvania Institutional Review Board(IRB) (PROTOCOL #834307).

Acknowledgments

The authors wish to admit Tim Cheney for his contributions to information management and analysis.

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