Evaluation of the psychometric properties of the ubacc questionnaire in assessing capacity to consent in diverse african populations by Kipkemoi, P, Mufford, M-A, Akena, D, Atwoli, L, Chibnik, L, Gelaye, B, Kariuki, S, Koenen, K, Newton, C, Post, K, Stein, D, Stroud, R, Teferra, S, Zingela, Z, Korte, K