​Laboratories play a critical role in HIV/AIDS clinical trials because they test all the study participants' blood or other samples for a variety of factors. Through this testing, researchers are able to determine:

• The integrity and usefulness of the samples
• How many HIV virions or "particles" are in the person's blood (viral load)
• How much damage has been done to the person's immune system (CD4 count)
• Blood levels of therapeutic drugs, such as antiretroviral drugs (for example, integrase inhibitors and protease inhibitors)
• The safety of a treatment through the measurement of a large number of indicators such as red blood cells, calcium, and blood sugar (glucose)
• The presence or absence of co-infections, such as tuberculosis (TB) or malaria

In short, the laboratories generate the scientific data that is analyzed in clinical trials. The data is submitted to a statistical and data management center (SDMC) such as Frontier Science & Technology Research Foundation (FSTRF) or the Statistical Center for HIV/AIDS Research and Prevention (SCHARP) for storage and analysis.