Study data was collected by trained designated staff and entered directly onto the appropriate Case Report Forms(CRFs) or in source documents. A study database was set up in OpenClinica, a web-based data management system and hosted at the MRC/UVRI clinical research centre. At each of the study sites, data was double entered by two separate data entry personnel. Data was entered as soon as possible (e.g. within one week) after a visit and routine data cleaning queries were raised and resolved. All data analysis was conducted in STATA V.18 (College Station, TX, US).