Mortality incidence estimation using federal death certificate and natality data with an application to Tay-Sachs disease

For confidentiality reasons, US federal death certificate data are incomplete with regards to the dates of birth and death for the decedents, making calculation of total lifetime of a decedent impossible and thus estimation of mortality incidence difficult. This paper proposes the use of natality data and an imputation-based method to estimate age-specific mortality incidence rates in the face of this missing information. By utilizing previously determined probabilities of birth, a birth date and death date are imputed for every decedent in the dataset. Thus, the birth cohort of each individual is imputed, and the total on-study time can be calculated. This idea is implemented in two approaches for estimation of mortality incidence rates. The first is an extension of a person-time approach, while the second is an extension of a life table approach. Monte Carlo simulations showed that both approaches perform well in comparison to the ideal complete data methods, but that the person-time method is preferred. An application to Tay-Sachs disease is demonstrated. It is concluded that the imputation methods proposed provide valid estimates of the incidence of death from death certificate data without the need for additional assumptions under which usual mortality rates provide valid estimates.