Visual analog scale of ART adherence: Association with 3-day self-report and adherence barriers

Background: Brief self-reports of antiretroviral therapy adherence that place minimal burden on patients and clinic staff are promising alternatives to more elaborate adherence assessments currently in use. This research assessed the association between self-reported adherence on visual analog scales (VASs) and an existing, more complex self-reported measure of adherence, the AACTG, and the degree to which each method distinguished optimally and sub-optimally adherent patients in terms of reported barriers to adherence. Methods: HIV-infected patients (N = 147) at a Southeastern US clinic completed a computerized assessment including an antiretroviral therapy adherence VAS, a modified version of the AACTG, and a measure of barriers to adherence. Results: Adherence rates were comparable across the AACTG (81%) and VAS (87%); they significantly correlated (r = 0.585) and produced identical classification of optimal (> 90%) or suboptimal (< 90%) adherence for 66% of patients. In general, VAS scores tended to be higher than AACTG scores. Suboptimally adherent patients reported more adherence barriers than those classified as optimally adherent, and those so classified by the VAS reported considerably more barriers to adherence than those so classified by the AACTG. Conclusions: Results generally support the construct validity of the VAS and its use as an easily administered assessment tool that can identify patients with barriers to adherence who might benefit from adherence support interventions.