The mean duration of gametocyte carriage was @ days ( @ % CI @-@ @ ) in the @ mg/kg reference group , @ days ( @-@ @ ) in the @ mg/kg primaquine group ( p = @ ) , @ days ( @-@ @ ) in the @ mg/kg primaquine group ( p = @ ) , and @ days ( @-@ @ ) in the placebo group ( p < @ ) .