Since the mid-1990s, antiretroviral (ARV) therapy (use of pharmacologic agents that have specific inhibitory effects on HIV replication) has become the standard regimen to achieve maximum viral suppression for people living with HIV.  Timing and regularity of dosing are essential to effectiveness; given the high frequency of HIV virus mutation, missing even a few doses can lead to increased viral replication, and potentially drug resistance and treatment failure. Therefore, adherence to prescribed ARV therapy medications must be monitored regularly to determine the level of adherence and to identify patients at risk for treatment failure.

Formula: The number of patients/clients with at least one HIV primary care visit in the past 12 months and a documented assessment of adherence to antiretroviral (ARV) therapy medications during the past 4 months. Divide by the total number of patients/clients with at least one HIV primary care visit in the past 12 months. Multiply by 100 to calculate percent.

Every month (or at the frequency established by your quality improvement effort), assess a random number of patient/client records. Select a sample of patients/clients on ARV therapy with an HIV primary care visit in the previous 12 months. Count the number of patients/clients with a documented adherence assessment in the past 4 months. Divide by the total number of patients/clients with at least one HIV primary care visit in the previous 12 months. Multiply by 100 to calculate percent. 

Note: The adherence assessment can be completed by appropriate members of the HIV care team, such as the clinician, nursing team, case manager, etc., and should include quantification of ARV medication adherence. Adherence quantification can be documented in percentages ("patient/client is 85 percent adherent") or number of medications taken over specific time periods ("patient/client took 7 out 10 medications in the last three days").

The National HIVQUAL Project’s Minimum Sample Table will help you determine the number of records to include in your sample. The Research Randomizer can generate a random number series to help you select which records to review.