Clinic-level factors influencing patient outcomes on antiretroviral therapy in primary health clinics in South Africa.

OBJECTIVES: To explore which clinic-level factors influence treatment outcomes in a multisite antiretroviral therapy (ART) programme in South Africa. DESIGN: Retrospective cohort study using 36 clinics. METHODS: We used random effects modelling to investigate clinic-level factors influencing ART outcomes, adjusting for patient-level factors and accounting for clustering at clinic level. Outcomes were unsuppressed viral load (>400 copies/ml) at 24 months after ART start and time to loss to follow-up. RESULTS: At clinic level, the mean proportion of patients with unsuppressed viral load at 24 months was 16% (range 8-33%). Loss to follow-up was also highly variable across clinics ranging from 3.5 to 23.4/100 person-years. Unsuppressed viral load was associated with a lower doctor-patient ratio [for every 500 patients, compared with >2.6 doctors: 6 interventions vs.