Patient and provider perceptions of a peer-delivered intervention (‘Khanya’) to improve anti-retroviral adherence and substance use in South Africa: a mixed methods analysis oleh Alexandra L. Rose, Jennifer M. Belus, Abigail C. Hines, Issmatu Barrie, Kristen S. Regenauer, Lena S. Andersen, John A. Joska, Nonceba Ciya, Sibabalwe Ndamase, Bronwyn Myers, Steven A. Safren, Jessica F. Magidson