Age-based targeting of biannual azithromycin distribution for child survival in Niger: an adaptive cluster-randomized trial protocol (AVENIR). - O'Brien KS; Arzika AM; Amza A; Maliki R; Ousmane S; Kadri B; Nassirou B; Mankara AK; Harouna AN; Colby E; Lebas E; Liu Z; et al. (BMC public health, 2021)