PopMod is a longitudinal population tool developed in 2003 that models distinct and possibly interacting diseases. Unlike other life-table population models, PopMod is designed to not assume the statistical independence of the diseases of interest. The PopMod has several intended purposes, including describing the time evolution of population health for standard demographic purposes (such as estimating healthy life expectancy in a population), and providing a standard measure of effectiveness for health interventions and cost-effectiveness analysis. PopMod is used as one of the standard tools of the World Health Organization's (WHO) CHOICE (Choosing Interventions that are Cost-Effective) program, an initiative designed to provide national health policymakers in the WHO's 14 epidemiological sub-regions around the world with findings on a range of health intervention costs and effects.