Source data
The register is built directly from the CMS Hospital Compare — Healthcare Associated Infections dataset, published by the Centers for Medicare & Medicaid Services and derived from the CDC's National Healthcare Safety Network (NHSN). The dataset covers every U.S. hospital that participates in CMS's Inpatient Quality Reporting program (effectively all acute-care hospitals receiving Medicare payment).
What's reported
Six measure families are reported per facility:
- CLABSI — Central Line Associated Bloodstream Infection (ICU + select wards)
- CAUTI — Catheter Associated Urinary Tract Infection (ICU + select wards)
- MRSA bacteremia — Methicillin-resistant Staphylococcus aureus bloodstream infection
- C. diff (CDI) — Clostridioides difficile infection
- SSI: Colon Surgery — Surgical site infection from colon surgery
- SSI: Abdominal Hysterectomy — Surgical site infection from abdominal hysterectomy
The Standardized Infection Ratio (SIR)
For each measure, the headline metric is the Standardized Infection Ratio (SIR) — the count of observed infections divided by the count of infections that would have been predicted given the hospital's case mix, size, and procedure volume. A SIR of 1.0 means the hospital saw exactly what was predicted; a SIR below 1.0 means fewer infections than predicted (better than expected); a SIR above 1.0 means more (worse).
Each SIR is published with a 95% confidence interval. CMS classifies a hospital as “Better than the National Benchmark” or “Worse than the National Benchmark” only when the entire confidence interval falls below or above 1.0 — i.e., the difference is statistically significant. Hospitals whose intervals cross 1.0 are classified as “No Different than the National Benchmark.”
Branmoor's risk classification
For each facility, Branmoor aggregates the six measure-level comparisons into a single signal:
- Elevated infection signal — worse than the national benchmark on 2 or more reported measures
- Mixed signal — worse than the national benchmark on exactly 1 reported measure
- Better than national — better than the benchmark on 2 or more measures and worse on none
- No elevated signal — otherwise
The aggregation is meant as a navigation aid, not a clinical judgment. The underlying CMS-published measure-level comparisons are the authoritative read.
Update cadence
CMS refreshes Hospital Compare HAI data quarterly. Branmoor re-ingests on each site deploy; the freshness is bounded by CMS's quarterly cadence. The reporting period for the current snapshot is shown on each facility page.
Limits
Two structural limits worth knowing:
- Reporting lag: the CMS dataset reflects infections from prior reporting periods (typically lagged 6–9 months). It is not real-time outbreak data. For active outbreak signal, the canonical sources are state health departments, which publish unevenly
- Reporting completeness: hospitals that do not perform a measured procedure type (e.g., no colon surgery) have no SSI: Colon measure. Hospitals below the CDC's minimum volume threshold for a measure are flagged as “not enough data available” rather than scored