In the 2017 version of CSAVR, we improved the tool by developing an approach to fitting incidence that uses Spectrum's AIDS Impact Model key assumptions and available information on number of new diagnoses, deaths and/or mean CD4+ at diagnosis to estimate incidence trends, mean time from infection to diagnosis, CD4+ at diagnosis and the proportion of people living with HIV who have been diagnosed over time. The gene discussed is CD4; the disease is infection.