The Vulnerable Elders Survey (VES), a screening tool for at-risk elderly, has been validated in the community. This study used VES-based criteria to develop a modified version that can be calculated from the Medicare Health Outcomes Survey (HOS) to identify Medicare members at high risk of mortality. Data were from 97,258 HOS respondents in 164 plans. Using age, self-rated health, and function items from the 2005 HOS, an a priori approach modeled on VES scoring and items predicted two-year mortality (c-statistic 0.74). Routinely-collected Medicare survey data may be used to assess patterns of enrollment of high-risk beneficiaries across health plans.