Matthew J. Press, M.D., M.Sc., Dennis P. Scanlon, Ph.D., Andrew M. Ryan, Ph.D., M.A., Jingsan Zhu, M.S., M.B.A., Amol S. Navathe, M.D., Ph.D., Jessica N. Mittler, Ph.D., and Kevin G. Volpp, M.D., Ph.D.
M. J. Press, D. P. Scanlon, A. M. Ryan et al., "Limits of Readmission Rates in Measuring Hospital Quality Suggest the Need for Added Metrics," Health Affairs, June 2013 32(6):1083–91.
Under the Affordable Care Act and other health reform initiatives, the federal government has begun implementing policies to encourage hospitals to reduce preventable readmissions of patients. Each of the policies holds hospitals primarily accountable for readmissions and assesses performance using risk-standardized readmission rates. Commonwealth Fund–supported researchers examined the change in readmission rates over a two-year period and the relationship between these rates and other commonly used measures of hospital quality.
Using the Centers for Medicare and Medicaid Services’ Hospital Compare website, the researchers examined hospital data on admissions for heart attack, heart failure, and pneumonia, dividing hospitals into quartiles based on performance. They found that the rankings fluctuated, with readmission rates for the lower-performing hospitals in 2009 improving by 2011 and the rates for the higher-performing hospitals worsening. The authors attributed this movement to “regression to the mean,” the statistical phenomenon in which values eventually move closer to the average.
Moreover, the study found weak or even inverse correlations between readmission rates and commonly used hospital quality indicators, such as 30-day mortality rates, volume of procedures performed, teaching status, and "process-measure performance"—the percentage of occurrences in which recommended care was provided to eligible patients.
Relying on readmission rates for a single period to identify hospitals of low quality could end up unfairly penalizing hospitals whose performance is driven by external factors, or hospitals that perform well on other quality measures. Policymakers, the authors say, should instead encourage hospitals to develop and use other measures of care transition quality. At the same time, a communitywide approach to the readmissions issue may be both more effective and more equitable.