Scoring Methodology

The Centers for Medicare & Medicaid Services (CMS) evaluates overall hospital performance under the Hospital-Acquired Condition (HAC) Reduction Program by calculating Total HAC Scores as the equally weighted average of scores across measures included in the program. Hospitals with a Total HAC Score greater than the 75th percentile of all Total HAC Scores (that is, hospitals in the worst-performing quartile) will receive a 1-percent payment reduction.

The HAC Reduction Program scoring methodology to calculate Total HAC Scores and determine which hospitals will receive a payment reduction includes the following steps:

Calculation of Measure Results

Determine the composite value for the CMS Patient Safety and Adverse Events Composite (CMS PSI 90) measure.
Determine the standardized infection ratios (SIRs) for the Centers for Disease Control and Prevention’s (CDC's) National Healthcare Safety Network (NHSN) healthcare–associated infection (HAI) measures.

Measure Score Calculation (Winsorized z-scores)

Winsorize measure results for each measure.
Calculate Winsorized z-scores, also known as measure scores, for each hospital using the hospital’s Winsorized measure results, national mean, and standard deviation of Winsorized measure results for each measure.

Total HAC Score Calculation (Equal Measure Weights)

Apply an equal weight for each measure for which a hospital has a measure score.
Multiply the measure score by the weight for each measure to obtain each measure’s contribution to the Total HAC Score.
Sum the contributions of the measure scores to obtain the Total HAC Score.

Worst-Performing Quartile Determination

Determine the 75th percentile of Total HAC Scores.
Classify hospitals with a Total HAC Score greater than the 75th percentile in the worst-performing quartile.

Additional Information and Resources

For more information on the current scoring methodology, refer to the HAC Reduction Program Scoring Methodology Infographic or the HAC Reduction Program Frequently Asked Questions document. For more information on the scoring methodology in previous years, refer to the HAC Reduction Program Frequently Asked Questions documents for previous program years. All of these materials are available on the Resources page.