Antiretroviral therapy (ART) for HIV requires strict regimen adherence. Motivational interviewing (MI) can improve ART adherence. MI process studies have rarely focussed on ART adherence. Such studies may facilitate MI modifications to improve outcomes. This study employed a single group pre and post-test design with 62 adults with HIV (16 female; mean age 40 years). Therapist use of MI-consistent (MICO) methods, MI spirit, and client change and sustain talk were coded from an MI session. Relationships were assessed with ART schedule adherence. MICO methods positively correlated with change and sustain talk and were negatively associated with proportion of change talk. No variables were associated with ART adherence change. Mediation analysis did not support the MI model of change. This may be due to the fact that ART adherence is determined by both motivational and non-motivational factors. It may also be that bidirectional relationships exist between therapist and client speech.
Keywords: Adherence; Antiretroviral; HIV; Mechanisms; Motivational interviewing.