c.2. Researchers are studying HIV prevalence using a cross-sectional study design. Which of the following factors may affect the researchers' assessment of HIV prevalence in their study population?...

Extracted text: c.2. Researchers are studying HIV prevalence using a cross-sectional study design. Which of the following factors may affect the researchers' assessment of HIV prevalence in their study population? Choose all that apply and explain your answer. a) Changes in HIV treatment b) Changes in HIV virulence (HIV virulence refers to the ability of the virus to cause disease) c) Population changes (e.g. migration) due to HIV infection, for example people who leave their community to live closer to physicians specialized in treating HIV d) Other factors which may affect survival of HIV-infected persons (e.g. changes in healthcare practices) e) Changes in HIV diagnostics f) Changes in HIV awareness and education