The impact on National Death Index ascertainment of limiting submissions to Social Security Administration Death Master File matches in epidemiologic studies of mortality.

Although many epidemiologists use the National Death Index (NDI) as the "gold standard" for ascertainment of US mortality, high search costs per year and per subject for large cohorts warrant consideration of less costly alternatives. In this study, for 1995-2001 deaths, the authors compared matches of a random sample of 11,968 National Institutes of Health (NIH)-AARP Diet and Health Study subjects to the Social Security Administration's Death Master File (DMF) and commercial list updates (CLU) with matches of those subjects to the NDI. They examined how varying the lower limits of estimated DMF match probabilities (m scores of 0.