Description: Presented at Living to 100 symposium, January 2011. Using data from Social Security's Death Master File, this study shows that mortality deceleration in humans observed at advanced ages may be an artifact caused by age exaggeration, data heterogeneity or use of improper estimates of hazard rate. The phenomenon of mortality deceleration at older ages vanishes for datasets of higher data quality.

Description: This article discusses the sources of the information in the Social Security Death Master File and the potential utility of this information for demographic studies of centenarians and near-centenarians.