Changes in Inpatient and Skilled Nursing Facility Care After the Medicare 3-Day Rule Reinstatement

Abstract

Importance:

On May 12, 2023 the Medicare program reinstated the longstanding 3-day hospitalization rule for skilled nursing (SNF) care after it had been waived for over two years during the COVID-19 pandemic. This abrupt policy change offers a natural opportunity to assess the contemporary impact of the rule on inpatient and post-acute care.

Objective:

To evaluate changes in inpatient length of stay, SNF utilization, spending, and short-term health outcomes among traditional Medicare beneficiaries following reinstatement of the 3-day hospitalization requirement.

Design, Setting, and Participants:

Retrospective cohort study of traditional Medicare beneficiaries with acute care hospitalizations between January and November 2023. A regression discontinuity design was used to examine changes in outcomes after the 3-day rule’s reinstatement.

Exposures:

Hospitalizations before vs on or after May 12, 2023.

Main Outcomes:

Primary outcomes were hospitalization for at least three days and SNF discharge. Secondary outcomes included 30-day rehospitalization, 30-day mortality, Medicare spending, and total SNF days.

Results:

This study included 332,044 unexposed hospitalizations (mean age, 78.3) and 338,375 exposed hospitalizations (mean age, 78.2) for traditional Medicare beneficiaries in 2023. Reinstatement of the 3-day rule was associated with a 1.13 percentage point increase (95% CI, 0.61-1.66 percentage points; p<0.001; relative change, 1.9%) in the likelihood of an inpatient stay lasting at least three days. Among patients discharged to SNFs, 3-day rule reinstatement increased the probability of an at least three-day hospitalization by 5.57 percentage points (95% CI, 4.91-6.24 percentage points; p<0.001; relative change, 6.4%). No significant changes were observed in the overall probability of SNF discharge, 30-day rehospitalization, 30-day mortality, Medicare spending or total SNF days. Subgroup analyses showed greater increases in at least three-day stays among patients hospitalized for hip fractures and patients with dementia.

Conclusions:

Reinstating Medicare’s 3-day hospitalization requirement was associated with longer inpatient stays without decreases in SNF utilization or improvements in short-term health outcomes. These findings suggest that the policy imposes additional costs on hospitals while failing to lower Medicare spending on hospitalized patients. More generally, results raise questions regarding the value and continued relevance of a broadly applicable 3-day inpatient stay rule in the traditional Medicare program.

Introduction

The longstanding 3-day hospital stay rule serves as a screening mechanism for ensuring that Medicare only covers skilled nursing facility (SNF) care for patients with short-term rehabilitation needs.¹ Under this rule, SNF care would be covered only if the Medicare beneficiary has a prior hospitalization of at least three consecutive days. While clinical necessity requirements are commonly used by health insurers to reduce overuse of care, clinicians and other scholars have raised concerns that the 3-day rule leads to inefficiencies and suboptimal patient care.^2,3 For instance, patients without a qualifying hospitalization may be discharged to less appropriate care settings. Hospital staffs may also extend inpatient stays unnecessarily to help patients meet eligibility requirements and avoid paying for SNF care out of pocket.² On the other hand, this rule may prevent some patients from being discharged prematurely since under Medicare’s prospective payment system hospitals are incentivized to discharge patients as early as possible.

One key barrier to reforming the 3-day rule is uncertainty about the clinical and economic impact of expanding SNF coverage to individuals with lower lengths of stay. The rule has been difficult to study since it has historically remained unchanged outside of alternative payment models.^4,5 In this study, we leveraged a natural experiment created by a federal policy change: the 3-day rule was temporarily waived during the COVID-19 PHE and reinstated on May 12, 2023, the day after the emergency officially ended.^6,7 This allowed us to identify changes associated with the 3-day rule by comparing outcomes between individuals who were subject to the rule because they were hospitalized immediately after the end of PHE with those hospitalized immediately before, when the rule was still waived. Specifically, we addressed two key questions about the impact of the 3-day rule. First, does the rule reduce the likelihood of discharge to SNF, or does it increase inpatient length of stay just above the 3-day threshold to ensure Medicare’s coverage of SNF care? Second, how may these changes affect patients’ short-term health outcomes?

Methods

Data sources

This study relied on the Medicare Beneficiary Summary File (MBSF), Medicare Provider Analysis and Review (MedPAR) data, and American Hospital Association (AHA) annual surveys from calendar years 2022 and 2023. The MBSF is an enrollment record of Medicare beneficiaries that captures demographics, insurance status, and dates of death. MedPAR includes 100% of all hospital and SNF claims for traditional Medicare beneficiaries and 90% of hospital claims for Medicare Advantage enrollees.⁸ The AHA provides organizational characteristics for hospitals nationwide. This study was approved by the Brown University institutional review board. The informed consent requirement was waived because study data were deidentified. The study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guidelines.

Study population

The study cohort included all traditional Medicare beneficiaries aged 65 and over with an acute hospital stay between January 1, 2023, to November 31, 2023. We excluded admissions in December due to the censoring of certain study outcomes. To account for transfers and contiguous stays, we combined continuous hospitalizations into a single stay and assigned patient and hospital characteristics from the final stay. We restricted the sample to new inpatient stays, defined as having no inpatient or SNF care within the 60 days preceding the hospitalization, to minimize the influence of prior care on study outcomes. We also identified a sub-cohort of individuals discharged to SNFs, since the 3-day rule is most relevant to patients with SNF care needs and may have a greater impact on outcomes in this population. This subgroup analysis would only be conducted if the rule was not associated with the likelihood of SNF discharge, which otherwise would lead to collider bias.⁹ For most analyses we focused on hospitalizations occurring within four weeks of the 3-day rule reinstatement date. Appendix Figure 1 illustrates the creation of our study population in further detail.

Main measures

The exposure of interest was the 3-day hospital rule. This rule was temporarily waived during the COVID-19 emergency and was administratively reinstated on Friday, May 12, 2023, the day after the PHE ended (Appendix A).^7,10 We defined a binary indicator for hospital admissions occurring on or after this date. We focus on the 3-day rule’s reinstatement rather than its waiver because the effects of the latter are difficult to distinguish from COVID-19-related changes in care utilization and health outcomes.

The primary outcome was whether the patient had three or more overnights in the hospital, operationalized with a binary indicator.¹¹ Another primary outcome was whether the patient had a SNF stay within 30 days of hospital discharge. Secondary outcomes were 30-day hospital readmission, 30-day mortality, the number of SNF days for patients admitted to SNFs, and Medicare spending — all of which could be affected by potential changes to either hospital length of stay or discharge setting. We counted the number of SNF days from the point of SNF admission through 100 days post to correspond with traditional Medicare coverage levels. Medicare spending included Medicare reimbursements for all hospital and SNF care within 100 days of index hospitalizations.

Statistical analysis

We first summarized the trends of outcomes within 16 weeks around the reinstatement cutoff date. We then used a regression discontinuity (RD) in time design to estimate changes in outcomes following the reinstatement of the 3-day rule.¹² The abrupt policy timing created a natural experiment that allows for the association between the 3-day rule and patient outcomes to be identified by comparing outcomes as they approach the policy date from each side; while outcomes are ordinarily expected to change “smoothly” over time, any sharp jumps in outcome rates corresponding to the cutoff date are attributable to the policy change. We restricted our sample to hospital admissions within 28 days around the cutoff date since observations within this narrow bandwidth are more comparable and the influence of seasonality become mitigated. In addition, our primary analyses used local linear triangular kernel regressions that assigned higher weight to observations closer to the cutoff date.

Each outcome was regressed on an indicator for pre- vs post-reinstatement adjusting for day of week, intensive care unit (ICU) admission, age, sex, race and ethnicity, dual Medicaid enrollment, the Elixhauser comorbidity index¹³, calendar time centered at the cutoff date, and the interaction of centered calendar time with the post-reinstatement indicator (Appendix B). In this specification the coefficient on post-reinstatement captures whether there were sharp changes in outcomes on the cutoff date associated with the reinstatement of the 3-day rule. We then stratified primary analyses according to various patient and provider characteristics since the 3-day rule may have heterogenous impacts. Patient subgroups included those with dementia, and those hospitalized for conditions that commonly precipitate post-acute care (pneumonia, chronic obstructive pulmonary disease [COPD], heart failure, and hip fracture). Appendix Table 1 lists the set of International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes used to identify the diagnostic sub-cohorts. Hospital subgroups were created based on teaching, rural, and proprietary status.

Sensitivity analyses

We performed multiple sensitivity analyses and falsification tests to support the RD design (Appendix C–M).¹⁴ First, we tested for changes in patient characteristics around the cutoff date, as the key assumption of RD is that all baseline characteristics other than the exposure are comparable or “smooth” at the cutoff. Second, we assessed potential manipulation of admission dates by testing the density of admissions around the cutoff. Third, we performed a donut hole robustness check, which tests the sensitivity of the main results to the exclusion of data close to the cutoff.¹⁵ This check further reduces any influence of potential manipulation around the cutoff and the influence of observations whose exposure status may be measured imprecisely. Fourth, we tested alternative bandwidths of 21 days through 49 days in 7-day intervals. Fifth, we used quadratic polynomials to test sensitivity of estimates to functional form changes. Sixth, as a falsification test, we used April 14, 2023, June 16, 2023, and May 12, 2022, as alternative cutoff dates, expecting no significant abrupt change in outcomes around other Fridays one month before or after, or on the same exact date one year earlier. Seventh, we created alternative outcomes of having a length of stay of exactly zero day and up to seven days to test whether changes in outcomes were specific to days closer to the cutoff as this rule should not affect longer hospital stays. Eighth, we used a data-driven method to select bandwidths around the cutoff date as an alternative to 7-day intervals.¹⁶ Ninth, we used difference-in-discontinuities to further account for any time-related confounding and enhance overall robustness. Tenth, we restricted analyses to hospitalizations following emergency department admission as well as hospitalizations without ICU utilization. Eleventh, we accounted for potential autocorrelations in the outcome data.¹²

Analyses were implemented using STATA version 18.0. All P values were 2-sided, and a threshold of P < .05 was used for statistical significance. Standard errors are clustered at the hospital level.

Results

Sample characteristics

We identified 332,044 (mean [SD] age; 78.3 [8.3] years) and 338,375 (mean [SD] age; 78.2 [8.3] years) hospitalizations within 28 days before and after May 12, 2023, respectively (Table 1). All baseline characteristics were balanced before and after the 3-day rule reinstatement except for dementia status (Appendix Table 2, panel B). Among hospitalizations before the reinstatement, 53.8% were female, 82.3% were White, and 16.3% were dually enrolled in Medicaid; 5.9% were hospitalized for heart failure, 1.5% for COPD, 3.4% for pneumonia, and 2.8% for hip fractures.

Table 1.

Characteristics of hospital admissions within 28 days of 3-day rule reinstatement, 2023

	Before May 12, 2023	On or after May 12, 2023	Standardized Difference e
N a	332,044	338,375
Age, sd b	78.3 (8.3)	78.2 (8.3)	0.0044
Female, % b	53.8	53.8	−0.0006
Black, % b	7.3	7.3	−0.0035
Hispanic, % b	5.2	5.3	−0.0020
White, % b	82.3	82.1	0.0045
Dual, % b	16.3	16.3	−0.0004
ICU admission, % c	30.0	30.0	−0.0008
Elixhauser index, sd c	9.4 (8.3)	9.4 (8.3)	−0.0026
Dementia, % c	9.2	9.1	0.0007
Heart failure, % c	5.9	5.8	0.0060
COPD, % c	1.5	1.5	0.0037
Pneumonia, % c	3.4	3.2	0.0111
Hip fracture, % c	2.8	3.0	−0.0116
Teaching, % d	20.7	20.7	0.0007
For-profit, % d	12.6	12.3	0.0092

COPD: Chronic Obstructive Pulmonary Disease; LOS: Length-of-stay; SNF: Skilled nursing facility.

^aThe main analytical sample included eligible acute hospitalizations within 28 days of May 12, 2023, among traditional Medicare beneficiaries.

^bDemographic information of patients was obtained from Master Beneficiary Summary Files (MBSF). Race and ethnicity were obtained from Research Triangle Institute’s race code.

^cHospitalization information was obtained from Medicare Provider Analysis and Review (MedPAR) data. Elixhauser comorbidity index was calculated using all diagnosis code on the MedPAR record; dementia status was identified using all diagnosis codes on the MedPAR record following Bynum standard algorithm; clinical conditions (heart failure, COPD, pneumonia, and hip fracture) were determined based on primary inpatient diagnosis.

^dHospital characteristics were obtained from 2023 American Hospital Association Annual Survey.

^eStandardized differences were calculated as the difference in means divided by a pooled standard deviation.³⁸ The standardized difference for binary variables is shown in the original scale (not multiplied by 100)/ The standardized difference is larger than the raw difference for binary variables.

Outcome trends before and after 3-day rule reinstatement

Figure 1 and 2 illustrates unadjusted trends of study outcomes near the 3-day rule reinstatement date. Except for the proportion of hospitalizations lasting at least three days, trends in all other outcomes were smooth and did not noticeably change around the reinstatement date for the entire hospitalized traditional Medicare sample (Panel A) and for individuals discharged to SNFs (Panel B). Importantly, trends in outcomes other than 3-day hospitalization exactly one year earlier were remarkably similar to trends in these outcomes around the actual 3-day rule reenactment date (Appendix Figure 2).

Figure 1.

Trends in health care utilization and health outcomes by days to 3-day rule reinstatement among all hospitalized traditional Medicare beneficiaries

Note: Only hospitalizations 112 days before and 105 days after the cutoff date were used to create the plot. This time window is wider than the bandwidth used to estimate primary regression discontinuity models to reduce noise. Each dot in the plot represents the average outcome within each seven-day bin. Dates were centered on the 3-day rule reinstatement date of May 12, 2023 (day 0). Quadratic polynomials were estimated separately using raw data to the left and to the right of the cutoff date.

Figure 2.

Trends in health care utilization and health outcomes by days to 3-day rule reinstatement among hospitalized traditional Medicare beneficiaries discharged to skilled nursing facilities

Note: Only hospitalizations 112 days before and 105 days after the cutoff date were used to create the plot. This time window is wider than the bandwidth used to estimate primary regression discontinuity models to reduce noise. Each dot in the plot represents the average outcome within each seven-day bin. Dates were centered on the 3-day rule reinstatement date of May 12, 2023 (day 0). Quadratic polynomials were estimated separately using raw data to the left and to the right of the cutoff date.

Regression discontinuity analyses of the 3-day rule

Among the full sample, the proportion with an inpatient stay lasting at least 3 days was 60.4% in the four weeks prior to 3-day rule reinstatement and 62.0% in the four weeks afterwards (Table 2). The adjusted change in the probability of an at least 3-day hospitalization was 1.13 percentage points (95% CI, 0.61-1.66; P<0.001; relative change, 1.9%). Among patients discharged to SNFs, the proportion with an inpatient stay lasting at least 3 days was 87.6% pre-reinstatement and 96.0% post-reinstatement. The adjusted change in the probability of an at least 3-day hospitalization for the SNF subgroup was 5.57 percentage points (95% CI,4.91-6.24; P<0.001; relative change, 6.4%). There were no significant changes in the overall probability of discharge to SNFs, 30-day rehospitalization rate, or 30-day mortality rate, or Medicare spending following 3-day rule reinstatement. The SNF discharge subgroup exhibited similar patterns in adverse outcomes as well as no noticeable change in the number of SNF days.

Table 2.

Regression discontinuity estimates on changes in length-of-stay, discharge location, and short-term outcomes after the 3-day rule reinstatement ^a

	Mean, before	Mean, after	Unadjusted differences	RD estimates (95% confidence interval) b
	All hospitalized traditional Medicare beneficiaries
At least 3-day LOS	60.4	62.0	1.63	1.13 (0.61, 1.66)
Discharge to SNF	18.9	19.0	0.14	−0.29 (−0.69, 0.11)
30-day rehospitalization	12.6	12.8	0.14	0.10 (−0.25, 0.45)
30-day mortality	4.9	5.0	0.04	0.12 (−0.10, 0.34)
Total Medicare spending, $ c	22257.1	22243.0	−14.07	104.94 (−168.32, 378.20)
	Discharged to SNF subgroup
At least 3-day LOS	87.6	96.0	8.44	5.57 (4.91, 6.24)
No. of SNF days	36.9	37.5	0.62	−0.09 (−0.77, 0.59)
30-day rehospitalization	21.7	21.6	−0.05	−0.22 (−1.20, 0.77)
30-day mortality	6.1	6.1	−0.04	0.41 (−0.16, 0.99)
Total Medicare spending, $	41729.2	42008.2	279.05	271.29 (−467.88, 1010.47)

LOS: length of stay; SNF: skilled nursing facility

^aHospital admissions within 28 days of the reinstatement date of the 3-day rule were used to estimate the model. Percentage points are reported for binary outcomes.

^bWe estimated a local linear model with triangular kernel weights. Each outcome was regressed on an indicator for on or after the reinstatement, a linear time trend, and an interaction between the indicator of reinstatement and linear time trend, adjusting for day of week, ICU admission, age, sex, race and ethnicity, dual Medicaid enrollment, and the Elixhauser comorbidity index. Standard errors were clustered at the hospital level.

^cMedicare spending includes Medicare reimbursements for all hospitalizations and skilled nursing facility care within 100 days following the hospital admission.

Changes in having at least 3-day stays varied across patient subgroups (Figure 3). Patients with dementia (2.20 percentage points; 95% CI, 0.62–3.78; P=0.006; relative change, 3.1%) and patients hospitalized for hip fractures (3.12 percentage points; 95% CI, 1.12-5.12; P=0.002; relative change, 3.6%) experienced the largest increase in hospitalizations lasting at least three days. However, changes in length of stay did not vary by hospital characteristics. There was no significant change in SNF discharge rates across all patient and provider subgroups.

Figure 3.

Regression discontinuity estimates on changes in hospital length of stay and skilled nursing facility discharge after the 3-day rule reinstatement across patient and hospital subgroups

COPD: Chronic Obstructive Pulmonary Disease; LOS: Length-of-stay; SNF: Skilled nursing facility.

Notes: Each effect was estimated using the main regression discontinuity model and a subset of hospitalizations with corresponding patient or hospital characteristics. Dementia, heart failure, COPD, pneumonia, and hip fractures are determined based on the primary diagnosis on index hospitalization claims. Teaching and for-profit status are determined based on American Hospital Association annual survey data in 2023. 4,326 (0.65%) hospital admissions were not matched to the survey data and were excluded from the subgroup analyses for teaching and for-profit status. Rurality of hospitals are determined based on the 2023 Rural-Urban Continuum Codes: hospitals in a nonmetropolitan county are categorized as rural. 11,662 hospital admissions (1.74%) were not matched to a rurality code and were excluded from the analysis.

Sensitivity analyses

The sensitivity analyses supported RD assumptions and the robustness of our results. First, although the density test suggested potential manipulation around the cutoff date (Appendix Figure 3), the RD failed to detect a change in daily number of hospitalizations at the cutoff date (Appendix Table 3). Second, the main results on at least 3-day hospital stays were robust to alternative bandwidths, donut holes, quadratic polynomials, use of data-driven bandwidths, the difference-in-discontinuities model, and autocorrelations (Appendix Tables 4–7; Appendix Figure 4). Third, our RD model failed to detect any changes in outcomes in our pseudo cutoff dates (Appendix Table 8). Fourth, the analysis of alternative length of stay cutoffs showed decreases in proportions of 1-day and 2-day stays, increases in 3-day stays, and no change in 4- to 7-day stays (Appendix Figure 5). This provided evidence that this rule was associated with increased hospital length of stay just above the threshold but not longer stays. Lastly, results were consistent in analyses restricting to admissions from the emergency department and removing admissions with intensive care unit utilization (Appendix Table 9).

Discussion

In this national study of traditional Medicare beneficiaries hospitalized from January to November 2023, we found that the reinstatement of the 3-day rule increased the proportion of hospitalizations lasting at least 3 days while having no discernable impact on SNF discharge rates. Changes to hospital length of stay were more pronounced for certain clinical subgroups, such as patients with dementia and those hospitalized for hip fracture. However, the association of the 3-day rule with SNF discharge rates was consistently null, including among those hospitalized for conditions that commonly require post-acute care. We also did not find evidence that the 3-day rule reinstatement was associated with short-term readmission or mortality rates, nor total SNF days.

This study provides rigorous empirical evidence that the 3-day rule may not serve its intended function of screening unnecessary post-acute SNF use and instead results in additional inpatient days that burden hospitals, clinical practice, and potentially patients. Using the lower and upper bounds of our RD estimate, we calculate that approximately 2,064 to 5,617 additional inpatient days occurred in the 28 days after the 3-day rule was reinstated. On the hospital side, the inefficient use of acute care beds increases costs on the facility not only by prolonging inpatient stays, but also potentially through additional diagnostic testing or treatments required to justify a 3-day hospitalization.¹⁷ In addition, excess bed occupancy can delay care and exacerbate health risks for patients who need inpatient care, which is especially concerning amid an ongoing hospital boarding crisis.^18–21 On the patient side, we did not observe significant downstream readmission or mortality changes, suggesting that the additional acute care days did not benefit patients clinically, nor that patients would be discharged prematurely without the three-day rule. Moreover, any excess amount of time spent in a hospital bed increases the marginal risk of adverse events including delirium, hospital-acquired infections, pressure injuries, and adverse drug reactions.^22–25 Some of these outcomes may occur in the SNF setting, however since total SNF days did not change, additional risks to patients introduced by the 3-day rule would be through extra hospital days.

The largest changes to inpatient length of stay were among patients actually discharged to SNFs. However, since overall SNF discharge rates were unchanged, our findings suggest that patients who would have been discharged to SNFs after a short inpatient stay (had the 3-day rule waiver remained in effect) were not redirected to other care settings. Instead, they stayed in the hospital longer to meet the 3-day requirement and did not compensate with fewer SNF days. One potential explanation for this is that, although longer length of stay correlates with SNF needs, the minority of SNF patients with short inpatient stays generally have appropriate indications for institutional post-acute care. Indeed, a variety of clinical conditions do not require extended hospital stays but result in deconditioning that may be best treated in a SNF; however, the 3-day rule delays access and may disrupt overall care delivery for patients with this profile.

There have been changes to the 3-day rule both within and outside of traditional Medicare. In traditional Medicare, the CMS Innovation Center has waived the rule for certain alternative payment models, but waivers have been used sparingly in these programs.^4,26 In MA, over 70% of plans have adopted a 3-day rule waiver.²⁷ A central argument against reforming the 3-day rule more broadly in traditional Medicare is the potential for increased spending on unnecessary SNF care.^2,28–30 However, our study indicates that that once a patient was admitted to a hospital, the 3-day rule has minimal impact on downstream SNF use. Therefore, policymakers may consider waiving the 3-day rule for inpatient admissions as a feasible starting point for reform with minimal fiscal and health impacts. Outside of the inpatient setting, however, the costs and benefits of removing the 3-day rule may differ and further consideration is warranted. For instance, although the frequency of admissions around the 3-day rule reinstatement was stable and suggests that observation stays were not converted to admissions at higher rates, there may have been a significant drop in SNF discharges directly following observation care. Relatedly, a recent study found that during the COVID-19 public health emergency, there were increases in SNF spending concentrated among nursing home residents who readily accessed SNF benefits without a prior hospitalization.³¹

Prior research on the 3-day rule has been focused on select hospitals, geographic regions, or Medicare Advantage plans.^32–36 Our findings are consistent with some of these previous studies,^32,35,36 but make a significant contribution through our analysis of comprehensive contemporary data, needed due to the likely permanent shifts to acute and post-acute care utilization post-pandemic. In addition, we use a strong quasi-experimental design that uniquely exploits a rare change to the 3-day rule in the Traditional Medicare program. However, our study has certain limitations. First, the regression discontinuity design can only estimate immediate effects at the time of the policy change; longer term studies are warranted. Second, the estimates may not generalize outside of hospitalized traditional Medicare beneficiaries. Third, other policy changes associated with the end of the public health emergency may have introduced confounding.⁵ However, only policies affecting length of stay near the three-day threshold could plausibly explain our findings. Finally, we could not rule out residual confounding, although we didn’t find any meaningful differences in patient characteristics before and after the policy change.

Conclusions

In this cohort study of hospitalized traditional Medicare beneficiaries, the reinstatement of the 3-day hospital rule for SNF care was associated with an increase in the proportion of hospital stays lasting at least three days, especially for patients who were discharged to SNF. In contrast, there were no discernable changes in SNF utilization, Medicare spending, or rates of short-term adverse outcomes. Because the policy appeared to prolong hospital stays without improving outcomes or achieving Medicare savings among inpatients, these findings raise questions regarding the value and continued relevance of a broadly applicable 3-day inpatient stay rule in the traditional Medicare program.

Key Points.

Question:

How did the reinstatement of Medicare’s 3-day hospital stay rule on May 12, 2023 impact inpatient and skilled nursing facility (SNF) care?

Findings:

In this retrospective cohort study of over 600,000 traditional Medicare hospitalizations, the 3-day rule’s reinstatement was not associated with changes in SNF discharge rates. However, the proportion of hospitalizations lasting at least three days increased by 1.13 percentage points overall and 5.57 percentage points among those discharged to SNFs.

Meaning:

Reinstating the 3-day rule lengthened hospital stays without reducing SNF use, suggesting that the rule’s broad application may be suboptimal.

Data Access, Responsibility, and Analysis:

Chen and Kosar had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis