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Why are death (mortality) rates for hospitals not shown in Hospital Compare?


HHS/CMS chose to only mark as outliers those hospitals that could be identified as different than the U.S. national rate with a high degree of certainty. Hospitals are only identified as better or worse than the U.S. national mortality rate if the 95% interval estimate for their risk-standardized mortality rate (RSMR) is completely above or below the U.S. national rate. Hence, the vast majority of hospitals are described on Hospital Compare as “No Different than the U.S. National Rate.”

The decision to use such a high confidence interval in this first iteration of the mortality measures was made to help hospitals get familiarized and comfortable with the measures and to maximize their usefulness in prompting quality improvement. It is possible that CMS will consider adjusting the confidence interval in future years to identify more hospitals that fall above or below the U.S. national rate.

Last Updated: 4/30/2008