Coping with multiple morbidity in a life table

One of the applications of the multi-state life table is in the field of Public Health, with states defining various levels of health or functional ability. Another approach is to model Public Health by looking at the impact of individual diseases, but, unfortunately, then two practical problems arise: there are many diseases, and due to comorbidity people may be in several diseases states simultaneously. Both problems tend to make the number of states in the life table unpractically large. In this paper we introduce the proportional multi-state life table. It is especially designed to cope relatively easily with a large number of diseases simultaneously, while allowing for comorbidity. We provide proof of validity and an example implementation for cardiovascular disease.