“…Studies were conducted in China (n 3), Nigeria (n 2), Mexico (n 2), Pakistan (n 2), Vietnam (n 2), Bangladesh (n 1), Indonesia (n 1), Cambodia (n 1), India (n 1), Kenya (n 1), Burkina Faso (n 1) and Bolivia and Madagascar (n 1). Eight studies were cluster-randomized controlled trials (28,29,31,32,35,36,44,45) , one was an individual-randomized controlled trial (40) , six were pre-post without a control group (33,34,38,(41)(42)(43) and three were pre-post with a control group (30,37,39) . The longest study duration was 4 years and the shortest was 9 weeks; the modal duration was 1 year (n 5).…”