BENEFITS OF LINKAGE TO THE NATIONAL DEATH INDEX IN THE LONGITUDINAL-STUDY OF AGING

To reduce the potential bias resulting from differential loss to follo w-up in the Longitudinal Study of Aging (LSOA), information obtained f rom household contact methods was supplemented with information from t he National Death Index (NDI). This article examines the degree of agr eement in the vital status data from two sources (reinterview contacts and the NDI system) and evaluates the potential gains of using the ND I data as a supplement to define participants' vital status. Results r eveal that NDI information, used to supplement reinterview information , can substantially reduce bias due to the differential loss of partic ipants to follow-up. Reliance on reinterview information alone was les s Likely to capture those deaths occurring in study participants who a t the initial contact lived alone, were below the poverty index, were interviewed without use of a proxy, did not supply a phone number, and did not own a home.