Multistate life tables: movement versus transition perspectives

This paper attempts to present a comprehensive view of the methodological and empirical aspects involved in the construction of increment - decrement life tables, that is life tables which allow entries into (increments) as well as withdrawals from (decrements) alternative states. The first principal part of the paper, section 2, presents a theoretical exposition of such tables, paralleling that of the ordinary life table, and discusses various issues raised by the conceptualization of multistate life-table functions. The second principal part, section 3, contrasts the two alternative approaches to the applied calculation of such tables. On the one hand, the movement approach, which views interstate transfers as events (such as deaths or births), requires data in the form of occurrence/exposure rates; on the other hand, the transition approach, which regards such transfers as the results of a change in an individual's state of presence between two points in time, uses data in the form of survivorship proportions.