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 the site, 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.