Overview
Measure Overview
The goal of this measure is to improve patient outcomes. Measurement of patient outcomes allows for a broad view of quality of care that encompasses more than what can be captured by individual process-of-care measures. Safely transitioning patients from hospital to home requires a complex series of tasks that would be cumbersome to capture individually as process measures: timely and effective communication between providers, prevention of and response to complications, patient education about post-discharge care and self-management, timely follow-up, and more. Suboptimal transitions contribute to a variety of adverse events post-discharge, including emergency department (ED) evaluation, need for observation, and readmission.
This Measures Under Consideration (MUC) submission includes an updated version of the AMI EDAC measure currently reported in the Hospital Inpatient Quality Reporting (Hospital IQR) Program. The updates include the addition of Medicare Advantage (MA) beneficiaries to the cohort, counting ED visits as 1 day and observation stays in rounded hours, using individual ICD-10 codes for risk adjustment, adopting a binomial model for estimating days in acute care.
Excess days in acute care after a hospitalization is an issue that affects patient outcomes and impacts the quality of care provided to patients. Measuring and reporting excess days in acute care provides transparency for consumers and informs health care providers about opportunities to improve care, strengthen incentives for quality improvement, and ultimately improve the quality of care (including better inpatient management of diabetes as well as better peri-discharge care quality) received by Medicare patients.
Measure currently used in a Medicare program, but the measure is undergoing substantive change.
Initially endorsed in 2016. Endorsed with conditions in Spring 2025 during maintenance review. Conditions request that when the measure returns in 5 years for maintenance endorsement, the developer would have empirically explored the differences with outpatient visits and post-hospitalizations for MA patients compared to fee-for-service patients.
Changes to the outcome weighting, addition of cohort, and changes to risk model.
Measure Specification
The outcome of the measure is a count of the number of days the patient spends in acute care within 30 days of discharge from an eligible index AMI hospitalization. We define days in acute care as days spent in an ED, or an observation stay, or admitted as an unplanned readmission for any cause to a short-term acute care hospital, within 30 days from the date of discharge from the index AMI hospitalization.
N/A
N/A
To be included in the measure cohort used in public reporting, patients must meet the following inclusion criteria:
- Have a principal discharge diagnosis of AMI;
- Enrolled in Medicare FFS Part A and Part B or MA for the first 12 months prior to the date of admission and enrolled in Part A or MA during the index admission. [For VA beneficiaries hospitalized in VA hospitals, there are no Medicare FFS or MA enrollment requirements. For VA beneficiaries hospitalized in non-VA hospitals, they must be concurrently enrolled in Medicare FFS Part A or MA at the time of the index admission, to be eligible for cohort inclusion, but the 12-month Part A and B or MA enrollment prior to admission is not required.];
- Aged 65 or over;
- Discharged alive from a non-federal short-term acute care hospital or VA hospital; and,
- Not transferred to another acute care facility.
N/A
The measure excludes index hospitalizations that meet any of the following exclusion criteria:
- Without at least 30 days of post-discharge enrollment in Medicare FFS or MA (in the case of patients who are not VA beneficiaries);
- Discharged against medical advice;
- Same day discharges;
- AMI admissions within 30 days of discharge from a prior AMI index admission
- Digital-Administrative systems: Administrative Data (non-claims)
- Digital-Administrative systems: Claims Data
Meaningfulness
Importance
The developer presents empirical data showing wide variability in days spent in acute care within 30 days after hospital discharge for patients hospitalized for AMI. Evidence from a literature review and standards of care review shows that hospitals can take interventional strategies to reduce days of acute care after discharge for patients with AMI. Reducing the need for acute care post discharge in patients with AMI aligns with national health priorities and demonstrates potential for improving outcomes.
The evidence supporting the importance of this measure was found to be sufficient during CBE endorsement review in 2025.
Conformance
This measure estimates days spent in acute care within 30 days post discharge from an inpatient hospitalization for AMI. The numerator includes emergency department visits, observation stays, and unplanned readmissions. The denominator includes patients aged 65 and older discharged from a hospital with a diagnosis of AMI. This measure aligns with the Hospital IQR Program objectives to improve the quality of care that hospitals provide and to distribute clearly defined and objective data about hospital performance.
Feasibility
No, not an eCQM
Data for this measure come from administrative data and claims data. These data sources are standardized and widely available across care settings. The measure can be implemented without significant workflow changes. The developer did not identify any technical barriers. The feasibility of this measure was found sufficiently demonstrated during CBE endorsement review in 2025.
Validity
Face Validity, Empirical Validity [MERIT Submission Form]
Facility
Yes
The developer assessed the empiric validity of the measure by comparing correlations between the AMI EDAC measure and components of the Overall Hospital Quality Star Rating, including the Readmission Group Score (with and without the Hospital-Wide Readmission measure), the Summary Score (with and without the entire Readmission Group), and the Patient Experience Group Score. Because the AMI EDAC measure follows a lower-is-better scale while Star Rating measures follow a higher-is-better scale, the developer hypothesized a weak to moderate negative correlation between the AMI EDAC measure and Star Rating-related measures.
The AMI EDAC measure showed negative correlations with the Star Rating Adjusted Readmission Group Scores (-0.252, p <.0001), the Star Rating Adjusted Summary Scores (-0.248, p < .0001), and the Star Rating Adjusted Summary Scores excluding the Readmission Measure Group Score (-0.122, p < .0001). These findings are consistent with expectations, reinforcing the relationship between lower AMI EDAC scores and higher Star Ratings as indicators of better quality of care.
The developer assessed the face validity of the measure score as an indicator of quality by surveying the technical expert panel (TEP) on their agreement on the following statement: the risk-standardized acute care days obtained from the measure as specified can be used to distinguish between better- and worse-quality hospitals. Eleven of the 12 members of the TEP agreed with the statement. However, the following three changes have been made to the measure since the TEP convened: the outcome weighting was simplified by assigning rounded times to observation stays and counting ED visits as 1 day, MA patients were added to the cohort, and the reporting period was shortened from 3 years to 2 years.
Testing in populations representative of the CMS program population supports the external validity of the measure.
The validity of this measure was found sufficiently demonstrated during CBE endorsement review in 2025.
The measure developer considered threats to validity during measure development and testing of a risk adjustment model. The measure is risk adjusted for patient functional status (frailty indicator), patient-level demographics (age), and patient-level health status and clinical conditions (case-mix adjustment, comorbidities, and severity of illness). The results of model discrimination testing and calibration using the c-statistic and examining predictive ability suggest that the model effectively differentiates excess days in acute care after hospitalization for heart failure levels and adequately adjusts for differences in patient characteristics.
Reliability
Random Split-Half Correlation [MERIT Submission Form]
Facility
The developer estimated the accountable entity-level reliability across multiple random split-half samples. The overall reliability estimate for hospitals with at least 50 admissions was 0.816. Reliability calculations used 2 years of data (2022-2023) from 1,741 facilities with at least 50 admissions. In collaboration on this PA evaluation, the developer provided the minimum, maximum, median, and 25th and 75th percentiles. Among hospitals with at least 50 admissions, the minimum reliability was 0.803, the median reliability was 0.816 (IQR: 0.813-0.819), and the maximum reliability was 0.834. All facilities exceeded the recommended minimum reliability threshold of 0.6.
During CBE endorsement review in 2025, the committee found the reliability of this measure to be sufficiently demonstrated.
No additional reliability analyses were conducted.
Usability
Yes, the submission materials briefly discuss the measure’s usability within the relevant program.
The measure is currently used in a CMS program and has demonstrated actionable insights for providers in the intended setting. According to the developer, no unintended consequences have been observed since its implementation, suggesting that the measure functions as intended without negatively impacting workflows or patient outcomes. This supports its continued use and indicates that it may be a reliable and beneficial tool for broader application.
The use/usability of this measure was found sufficiently demonstrated during CBE endorsement review in 2025.
Appropriateness of Scale
Overview
- Excess Days in Acute Care (EDAC) after Hospitalization for Pneumonia is a related measure in the Hospital IQR Program and Hospital Readmissions Reduction Program.
- Excess Days in Acute Care (EDAC) after Hospitalization for Heart Failure (HF) is a related measure in the Hospital IQR Program and Hospital Readmissions Reduction Program.
- Hospital 30-Day, All-Cause, Risk-Standardized Readmission Rate (RSRR) Following Acute Myocardial Infarction (AMI) Hospitalization is a related measure in the Hospital Readmissions Reduction Program.
The measure is well-suited for use across diverse populations and care settings, with minimal burden and high value. While the Hospital IQR Program has several similar measures, the program has no competing measures. The measure captures EDAC from ED visits and observation stays as well as readmissions. This represents an important construct to patients. The EDAC measures each capture excess days in acute care following hospitalizations for different conditions and complement one another to achieve program goals.
Considerations for the committee: Based on clinical and professional experience, the committee should consider how different populations might benefit from use of the measure and whether the measure will have the same impact in rural or low-resource settings.
Time to Value Realization
Overview
Yes, the developer briefly addresses near-term impacts on patients and measured entities.
From a patient perspective, days in acute care from any cause is an adverse event. The purpose of this measure is to encourage hospitals to collaborate with their communities to reduce days in acute care. The measure also supports CMS’s goals of enhancing patient safety, reducing readmissions, and improving overall health care efficiency.
Considerations for the committee:
- What are the potential near- and long-term impacts of this measure on measured entities, the Hospital IQR Program, and patient populations?
- Will benefits and burdens associated with this measure be realized within an appropriate implementation time frame?
- How will this measure continue to mature through revisions in the Hospital IQR Program?
Public Comments
MUC2025-030
The Kansas Hospital Association has concerns regarding the substantive changes identified in this measure.
The inclusion of Medicare Advantage (MA) beneficiaries raises concern, as hospitals have limited ability to account for or influence MA plan utilization management policies, including prior authorization requirements, network limitations, and post-acute care restrictions. These plan-level factors may affect utilization outcomes in ways that are unrelated to hospital performance and could introduce variability that is outside the hospital’s control.
We also have concerns regarding the inclusion and weighting of emergency department (ED) visits and observation stays. Counting ED visits as a full day and observation stays based on hours, rounded up to one day, may overstate utilization and inadvertently penalize hospitals for clinically appropriate care delivered in lower-acuity settings. ED and observation services should not be treated as equivalent to inpatient days, as this may discourage appropriate care pathways and conflict with CMS goals related to care efficiency and right-site care.
We recommend reconsideration of the inclusion of MA beneficiaries in the cohort and exclusion of ED and observation stays from utilization calculations to ensure the measure more accurately reflects hospital performance.
EDAC AMI
Understand the value of EDAC for pneumonia and heart failure, however returns to ED or observation status do not usually have the same frequency for this condition. Question EDAC value vs. raw readmission using admission days only.
SHM continues to oppose…
SHM continues to oppose using 30-day windows with the Excess Days in Acute Care measures. Current evidence suggests that the window of impact for preventing readmissions or returns to the ER is much shorter than 30 days, and may be as short as 7 days. Therefore, the measure as structured makes hospitals and clinicians accountable for factors well outside of their control. We urge CMS to narrow the episode window for these measures to focus on the modifiable factors within hospitals and clinician’s control to prevent or reduce excess days in acute care.
Chin DL, Bang H, Manickam RN, Romano PS. Rethinking Thirty-Day Hospital Readmissions: Shorter Intervals Might Be Better Indicators Of Quality Of Care. Health Aff (Millwood). 2016 Oct 1;35(10):1867-1875. doi: 10.1377/hlthaff.2016.0205. PMID: 27702961; PMCID: PMC5457284.
EDAC- AMI
As the agency did in last year’s PRMR process, CMS included this updated measure on the MUC list because it intends to include MA beneficiaries in the denominator. We appreciate the general effects this change would have to improve accuracy of the measure, but it is unclear from the supporting documentation whether any analysis has been done to determine the implications of including these beneficiaries for the outcomes of the IQR program. We hope that the measure developer can provider additional insight into how the change to the measure’s specifications would impact performance on the EDAC measures.
MUC2025-030 EDAC after hospitalization for AMI
On behalf of the American Heart Association, including the American Stroke Association (Association) and 35 million volunteers and supporters, we appreciate the opportunity to submit comments on MUC2025-030. The Association supports the updated specifications expanding measurement to MA beneficiaries to the cohort.
MUC2025-030*, EDAC after Hospitalization for AMI
We recommend refinements to ensure the measure accurately reflects hospital quality and does not penalize appropriate care. CMS should assess whether counting each ED visit as a full “day” overstates acute-care use for low-intensity encounters and publicly share impact analyses of this modeling choice. Some post-discharge ED visits and observation stays reflect appropriate monitoring, medication adjustments, or limited outpatient access rather than failures in inpatient care or discharge planning.
Post-discharge acute-care use is strongly influenced by social risk, outpatient access, and local practice patterns. Stratified reporting by dual-eligible status or other social risk indicators, geography (urban vs. rural), and PCI versus non-PCI AMI would help distinguish care-transition gaps from broader system-level access challenges and support more targeted quality improvement.
The ACC supports efforts to improve risk-adjustment granularity, including the use of individual ICD-10 codes to better capture disease severity and comorbidity burden. However, reliance on granular coding increases vulnerability to coding variation, providing some hospitals with more sophisticated coding infrastructure an advantage without reflecting true clinical differences. CMS should evaluate this risk and ensure transparency by publishing the ICD-10 codes included in the model and their relative weights. Because diagnosis codes alone do not capture key clinical severity markers, CMS should also explore incorporation of validated clinical registry data.
Adding MA beneficiaries raises important questions about data completeness, outpatient access, and coding comparability. CMS should evaluate MA versus fee-for-service differences in post-discharge follow-up, specialty care access, and cardiac rehabilitation use to ensure the measure does not inadvertently reflect access barriers rather than hospital quality or widen existing disparities.
We recommend the following refinements to strengthen clinical relevance and fairness:
Comments on MUC2025-030
Addition of Medicare Advantage Data
Vizient appreciates efforts to update the MUC2025-030: Excess Days in Acute Care (EDAC) after Hospitalization for Acute Myocardial Infarction (AMI) measure by adding Medicare Advantage (MA) population data as more than half of Medicare patients are covered through MA plans. While Vizient recognizes the importance of updating quality measures to reflect a broader range of Medicare beneficiaries, we continue to believe that additional steps are needed to ensure that MA data can be used reliably alongside fee-for-service (FFS) data. For example, as noted in Vizient’s FY 2026 IPPS Proposed Rule comments, there may be differences in how FFS claims and MA encounter data are recorded, yet it does not appear that an analysis to identify the impact of these types of differences has been completed. Vizient encourages P4QM to consider our recommendation that CMS analyze the data to ensure encounter data is accurate and comparable between FFS and MA before including MA beneficiaries in these measures.
In addition, another important consideration is that MA populations can vary significantly across plans, and in some cases may be selectively healthier. Without careful attention to appropriate risk adjustment, these differences could unintentionally bias performance results. Ensuring that MA data are risk‑adjusted correctly is essential for fair and meaningful comparisons across hospitals.
Increasing Emergency Department and Observation Stays to One Day
CMS is also considering changing the MUC2025-030: Excess Days in Acute Care (EDAC) after Hospitalization for Acute Myocardial Infarction (AMI) measure specifications to increase the count for Emergency Department (ED) visits from 0.5 days to one full day, and to calculate observation stays (OBSs), based on the total hours spent in observation, by rounding that time up to one full day. Vizient agrees with this change of counting ED visits and OBSs to one day and plans to use this timeframe for future benchmarking work. This update will also help improve consistency among measures.
Comment re: MUC2025-030
We request transparent model specifications, transition periods, and social risk adjustment to avoid penalizing hospitals serving vulnerable populations.
Premier supports the…
Premier supports the addition of Medicare Advantage (MA) members and the technical changes proposed for the Excess Days in Acute Care (EDAC) measures. Premier remains concerned that the EDAC measures may not be easily replicable using available data sources. With respect to the EDAC measure for Acute Myocardial Infarction, Premier has observed that the volume tends to be so low that smaller hospitals do not report this measure due to minimum volume thresholds.
Premier also has concerns about the ability of these measures to improve hospital quality when the data lags by two years. This can impact both the observed performance by not reflecting today’s outcomes and risk adjustment by using older data to create expected values for more recent patients. Premier has also observed that the risk standardized results do not change much over time and may not reflect performance improvement because it is heavily driven by the random effect in the model. The use of the Predicted to Expected ratio rather than the Observed to Expected ratio, while helpful to reduce undue influence from outliers, does not provide a good reflection of actual performance. Consequently, CMS should emphasize that this methodology is best suited for payment purposes and not quality improvement purposes. The utility of the measure is further hindered by the facility level hierarchical methodology, which does not allow for drill downs into further subgroups, e.g. by physician grouping.
MUC2025-030
Support with modifications: Recommend stratification and clear attibution. Recommend focusing on TRC and PCR vs adding new measure (seems duplicative). Would appreciate more information on why these diagnosis are split out (MI/HF/Pneumonia/Diabetes, etc.).
Excess Days in Acute Care (EDAC) after Hospitalization for AMI
The American Occupational Therapy Association (AOTA) supports the updates to the Excess Days in Acute Care after Hospitalization for Acute Myocardial Infarction (AMI) measure. Seeking care after hospitalization for AMI increases healthcare costs and can be highly disruptive for patients. AOTA strongly supports the addition of the Medicare Advantage (MA) cohort to this measure. MA enrollment has steadily increased, and excluding this population fails to provide a complete picture for public reporting.
Patients and healthcare practitioners, including occupational therapy (OT) practitioners, consistently report that MA plans often delay, deny, or limit needed care to reduce hospital readmissions. Including MA data will improve the accuracy of public reporting, highlight discrepancies in outcomes based on coverage, and hold MA plans accountable to ensure patients receive necessary care.
OT services during a hospital stay and after a hospital discharge can be critical to avoiding hospital readmissions. OT practitioners address functional limitations, promote safe transitions, and support engagement in essential daily activities – factors that contribute to recovery and overall well-being.
An independent study found that OT services were the only spending category with a statistically significant association with lower readmission rates for heart failure, pneumonia, and AMI (Rogers et al., 2016). However, some MA policies may limit or exclude critical OT services. Capturing MA data for excess days in acute care after hospitalization for AMI is an important step toward ensuring all Medicare beneficiaries, traditional and MA, have access to the services and tools needed to optimize recovery and well-being after a hospital stay.
Reference:
Rogers, A. T., Bai, G., Lavin, R. A., & Anderson, G. F. (2016, September 2). Higher hospital spending on occupational therapy is associated with lower readmission rates. Medical Care Research and Review, 1–19. https://doi.org/10.1177/1077558716666981