Age patterns of marital fertility: Revising the Coale–Trussell method

This article revises the Coale–Trussell method for analyzing data from the World Fertility Survey by proposing and testing alternative log-linear and log-multiplicative models. The models, in one form or another, represent the structural constraint underlying the Coale–Trussell method on the variation in the age pattern of human fertility. With a Poisson distribution assumption for the number of births, several parameters of the models are simultaneously estimated via maximum likelihood. It is shown that the new approach can be adopted whenever fertility limitation is compared across multiple populations or subpopulations. Future users of the Coale–Trussell method for single populations or subpopulations are advised to use the new v_a estimates from this study in place of those of Coale and Trussell.