What Is the Value of Adding Medicare Data in Estimating VA Hospital Readmission Rates?

Objective To determine the effects of including diagnostic and utilization data from a secondary payer on readmission rates and hospital profiles. Data Sources/Study Setting Veterans Health Administration ( VA ) and Medicare inpatient and outpatient administrative data for veterans discharged from 153 VA hospitals during FY 2008–2010 with a principal diagnosis of acute myocardial infarction, heart failure, or pneumonia. Study Design We estimated hospital‐level risk‐standardized readmission rates derived using VA data only. We then used data from both VA and Medicare to reestimate readmission rates and compared hospital profiles using two methods: Hospital Compare and the CMS implementation of the Hospital Readmissions Reduction Program ( HRRP ). Data Collection/Extraction Methods Retrospective data analysis using VA hospital discharge and outpatient data matched with Medicare fee‐for‐service claims by scrambled Social Security numbers. Principal Findings Less than 2 percent of hospitals in any cohort were classified discordantly by the Hospital Compare method when using VA ‐only compared with VA /Medicare data. In contrast, using the HRRP method, 13 percent of hospitals had differences in whether they were flagged as having excessive readmission rates in at least one cohort. Conclusions Inclusion of secondary payer data may cause changes in hospital profiles, depending on the methodology used. An assessment of readmission rates should include, to the extent possible, all available information about patients' utilization of care.