In view of the article by A. Khalili, and coauthors,1 we thought it might be interesting to present an alternative way of looking at the estimation of the rate of malformation from multiple sources. Also, we will present some new data on the rates of congenital malformation in New York State.
When death certificates are matched to birth certificates, three possible outcomes exist with respect to congenital malformations. The malformation will be noted on both the death and birth certificates, it will be included on the birth certificate only, or on the death certificate only.