A Markov process interpretation of Sullivan's index of morbidity and mortality.

Using intuitive arguments Sullivan described a method of combining morbidity data and certain ordinary life table to produce an estimate of illness-free life expectancy. In this paper we use an increment-decrement life table specified in terms of a Markov process to characterize illness-free life expectancy. We show that when the illness under consideration satisfies certain properties Sullivan's approach provides a convenient method of approximation. We illustrate theoretical results with hospital morbidity data on Canadian males for 1981.