Every day, hospitals are being asked to provide a higher level of care for higher-acuity patients with fewer resources. In an era of rising complexity, benchmarking, shared learning and forecasting are essential practices to turn data into actionable insights. Through these efforts, health systems can identify opportunities and improve access, quality and efficiency, as well as anticipate change and mitigate risks across the System of CARE (clinical alignment and resource effectiveness).
America’s Essential Hospitals (AEH) members (“essential hospitals”) represent nearly 400 organizations delivering high-quality care to all people, including those facing social and financial barriers. AEH makes up approximately 5% of the nation’s hospitals but provides 28% of charity care nationally. These hospitals lead in advancing access and innovation, training the healthcare workforce and driving improvements in outcomes—while sharing a safety net mission to care for all people.
Analysis of 123 essential hospitals in the Vizient Clinical Data Base (CDB) shows that essential hospitals consistently deliver efficient, high-quality care despite treating more complex patients. All analyses include only continuously reporting hospitals for both the AEH cohort and total CDB hospitals, covering the time frame from Q4 2021 to Q2 2025.
Figure 1. Comparative inpatient performance: AEH vs. total CDB hospitals, Q1 2025
*Readmission risk models begin in Q4 2020. Data trends for ALOS and mortality (observed/expected) % change are from Q4 2019 to QI 2025. Data trends for 30-day readmissions are from Q4 2020 to QI 2025. Note: Analysis excludes 0-17 age group. Indices are ratios of observed-over-expected values with expected values calculated based on Vizient risk-adjusted models. AEH = America’s Essential Hospitals; ALOS = average length of stay; CDB = Clinical Data Base; CMI = case mix index; IP = inpatient. Source: Data from Vizient Clinical Data Base used by permission of Vizient, Inc. All rights reserved.
- Essential hospitals experienced a 7.1% increase in inpatient discharges since 2019, representing a 42% higher growth than total CDB hospitals. Their case mix index (CMI) (2.85 vs. 1.80) and 60% higher expected average length of stay (ALOS) (9.67 vs. 6.03) underscore the more complex, high-acuity population they serve.
- Essential hospitals’ observed and expected ALOS are aligned, indicating effective management of higher-acuity patients consistent with expectations for their case mix. In contrast, overall CDB hospitals have a lower observed ALOS (5.48) compared to the expected ALOS (6.03), demonstrating stronger throughput performance relative to their population’s risk level. Both groups have shown continued improvement in their LOS index, reflecting reductions in observed ALOS relative to expected performance.
- Both groups demonstrated lower-than-expected mortality rates and substantial improvement in this index over time, with observed-to-expected mortality decreasing by 24.7% for essential hospitals and 25.8% for all hospitals.
- Thirty-day unplanned readmissions are 17.4% at essential hospitals versus 11.3% across CDB hospitals, both exceeding expected rates. Data trends underscore this as a key opportunity for performance improvement through strengthened post-acute care coordination to improve quality outcomes and capacity.
Essential hospitals manage high-vulnerability populations
Figure 2. Inpatient utilization trends by Vizient Vulnerability Index (VVI)
Note: Analysis excludes 0-17 age group. AMC 2023 risk model used. High VVI>I; average VV-I to I; low VM-IV calculated based on patient origin five-digit ZIP code. Sources: Data from Vizient Clinical Data Base used by permission of Vizient, Inc. All rights reserved, Vizient Vulnerability IndexTM Patent Pending. Copyright Vizient Inc. 2022. All rights reserved.
The communities AEH hospitals serve were analyzed using the Vizient Vulnerability Index (VVI). The VVI assesses nine social drivers of health and the overall vulnerability index for each census tract and ZIP code across the U.S., which are calculated as standard deviations from the national mean. The nine drivers of health are economics, housing, education, social environment, neighborhood resources, public safety, healthcare access, transportation and clean environment. Any score greater than1 is considered an area of “high vulnerability.”
- Across the three VVI categories, essential hospitals maintain a consistently higher CMI than the CDB hospitals, with the highest CMI among CDB hospitals remaining below the lowest for the essential hospitals. This underscores essential hospitals’ role in caring for higher-acuity, more complex patients.
- Despite this complexity, mortality indices for essential hospitals remain below expected levels across all VVI categories, reflecting strong clinical performance despite serving patients with significantly higher social needs.
- LOS indices also are in line with expected levels across all VVI categories, suggesting efficient patient management regardless of vulnerability categorization.