Voluntary Disenrollment from Part C and D plans: Variation across plan types and beneficiary profiles

Medicare Options Compare and the Medicare Prescription Drug Plan Finder provide plan sponsor rating information for beneficiary use in choosing their Medicare Advantage or Prescription Drug plan. CMS had relied on a disenrollment survey to measure voluntary disenrollment, an indication of a plan's enrollment turnover and potential beneficiary dissatisfaction, but after the survey was discontinued in 2005, information on voluntary disenrollment has been non-existent.

This paper presents findings from a study funded by CMS to develop plan performance and monitoring measures on voluntary disenrollment. This information is expected to further guide beneficiary's selection a plan for CY2010 as well as to serve as an administrative tool for monitoring plan performance.

Based on data administrative data on all MA and PDP beneficiaries for CY2008, we develop several measures of voluntary disenrollment for active CY2009 contracts. The analysis was based on identification of valid codes that identify voluntary disenrollment in the Part D and the Part C programs for the first disenrollment since multiple disenrollments are allowed for certain populations. Based on our aggregate calculation, 10.7% of beneficiaries voluntarily disenrolled at some point during 2008 (either during the year or at the end of the year) while 9.6% disenrolled form Part D plans. Similar values were found when the measures were presented at the contract level. Voluntary disenrollment rates varied by contract size and contract type, with the smallest contracts and PFFS contracts having the highest rates of voluntary disenrollment. This paper furthers explores these measures by statistically controlling for plan types and beneficiary profiles (Low-Income Subsidy status) and regional differences.