Monitoring retention in care: using multiple laboratory tests as an indicator for HIV medical care.

Retention in care is an important strategy for HIV prevention. Unfortunately, surveillance systems were not designed to capture face-to-face visits with HIV health care providers to assess retention in care. Instead, HIV-related laboratory tests are used as a surrogate measure. This study estimated the sensitivity (90%) and specificity (28%) of two HIV-related laboratory tests separated by at least 90 days for two face-to-face visits among people receiving HIV-related health care in Oregon. Overall accuracy of the surrogate was good but slightly overestimated the proportion of people living with HIV/AIDS actually retained in care.