OHD Learn · Hospital Quality Programs

Unplanned Hospital Visits

How often patients return to a hospital within 30 days of discharge — by condition, by procedure, and hospital-wide. Readmissions and excess days in acute care.

⭐ Feeds Overall Star Rating 💰 Feeds HRRP Payment 📅 Updated annually
What This Program Covers

What happens after a patient leaves matters as much as what happened during the stay.

An unplanned return to a hospital within 30 days of discharge is a signal that something went wrong — either the patient was discharged too soon, wasn't adequately prepared for recovery, didn't receive proper follow-up care, or deteriorated in ways that a well-managed discharge might have prevented. CMS measures this in two ways: 30-day readmission rates by condition and procedure, and a newer metric called Excess Days in Acute Care (EDAC) that captures returns that don't rise to the level of an inpatient admission.

All readmission measures are risk-standardized — a hospital treating sicker or more complex patients is expected to have higher readmission rates, and the comparison accounts for that. The rate is compared to what would be expected for a hospital with the same patient mix.

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Star Rating + Payment Connection
Readmission measures populate Group 3 (Readmission) of the Overall Hospital Star Rating. A subset of condition-specific readmission rates also determine penalties under the Hospital Readmissions Reduction Program (HRRP) — up to 3% on all Medicare inpatient payments for hospitals with excess readmissions.
The Measure Set

By condition, by procedure, and hospital-wide.

By Medical Condition
30-day unplanned readmission rates · 36-month collection
Estimates of unplanned readmission to any acute care hospital within 30 days of discharge for patients treated for these conditions. Each is risk-standardized and compared to the national rate.
  • Heart attack (AMI)
  • Heart failure
  • Pneumonia
  • Chronic obstructive pulmonary disease (COPD)
  • Stroke
By Procedure
30-day unplanned readmission rates · 36-month collection
Readmission rates following specific elective and semi-elective procedures. These populations are more homogeneous than medical admissions, making comparison more reliable.
  • Coronary artery bypass graft (CABG) surgery
  • Total hip / knee replacement (THA/TKA)
  • Outpatient colonoscopy (hospital visit rate)
  • Outpatient chemotherapy (hospital visit rate)
  • Outpatient surgery (hospital visit ratio)
Hospital-Wide Readmissions
30-day unplanned readmission · 12-month collection
The hospital-wide readmission measure encompasses all eligible medical, surgical, gynecological, neurological, cardiovascular, and cardiorespiratory admissions — not just specific conditions. It provides the broadest view of a hospital's discharge quality and post-discharge care coordination.
  • All eligible inpatient admissions
  • Risk-standardized 30-day unplanned readmission rate
  • Compared to national rate
Excess Days in Acute Care (EDAC)
Days per 100 discharges · 36-month collection
EDAC captures returns to acute care that don't meet the threshold for an inpatient readmission — ED visits, observation stays, and short inpatient stays. It counts the total days spent in acute care settings within 30 days of discharge, reported as days per 100 discharges above or below zero.
  • AMI excess days in acute care
  • Heart failure excess days in acute care
  • Pneumonia excess days in acute care
Reading EDAC Results

EDAC is expressed in days, not percentages — and can be negative.

Unlike readmission rates — which are percentages compared to a national average — EDAC results are expressed as days per 100 discharges relative to zero. Zero represents what would be expected for an average hospital with the same patient mix. A negative number is better; a positive number is worse.

Excess Days in Acute Care (EDAC) — How to read the number
Reported as days per 100 discharges, relative to what an average hospital with the same case mix would produce.
−4.2 days
Better than expected
Patients spent 4.2 fewer days in acute care per 100 discharges than expected. The hospital's post-discharge care coordination is above average for this condition.
0.0 days
Exactly as expected
The hospital's patients spent exactly as many days in acute care as the model predicted for this patient mix. Performance is in line with the national average.
+6.8 days
Worse than expected
Patients spent 6.8 more days in acute care per 100 discharges than predicted. This hospital's patients are returning to acute care settings more than expected after discharge.
Sources
  1. CMS Hospital Downloadable Database Data Dictionary, January 2026 — CMS Provider Data Catalog
  2. Readmissions Measures Methodology Reports — QualityNet.cms.gov
  3. EDAC Measure Methodology Report — QualityNet.cms.gov