Probabilistic Projections of Mortality in Countries with Generalized HIV Epidemics for Use in Total Population Projection

David J. Sharrow, University of Washington
Yanjun He, University of Washington
Adrian Raftery, University of Washington

The UN issued probabilistic population projections for all countries for the first time in July 2014. This was done by simulating future levels of fertility and life expectancy from Bayesian hierarchical models, and combining the results using a standard cohort-component projection method. The 40 countries with generalized HIV/AIDS epidemics were treated differently, in that the projections used the highly complex multistate Spectrum/EPP model designed for short-term projections of quantities relevant to policy. We propose a simpler approach that is more compatible with existing UN projection methodology for other countries. We project changes in life expectancy probabilistically using a time series regression and then convert to age-sex-specific mortality rates using model life tables designed for countries with generalized HIV/AIDS epidemics. The rates are then input to the standard cohort-component method, as for other countries. The method performed well in validation experiments. It gives similar projections to Spectrum/EPP, while avoiding multistate modeling.