Study design
This was a randomized open label trial carried out between July 2020 and June 2021. The study protocol was published previously [Included children were randomly assigned following a computer-generated randomization list to one of the three study arms SMC + Vitamin A (SMC-A) or SMC + Vitamin A + Zinc (SMC-AZc) or SMC + Vitamin A + PlumpyDoz™, (SMC-APd) a Medium Quantity Lipid-based Nutrient Supplement. Single dose of 200000UI of Vitamin A per child was administered within 3 weeks preceding the start of SMC campaign. One sachet of PlumpyDoz™ (Nutriset, Malaunay, France) was offered daily over a period of 3 months while 10 mg of elemental Zinc was administered daily in 6 days per week for the same period as for PlumpyDoz™ (3 months). The supply of nutritional supplements was done every two weeks and at each contact during monthly home visits. The first dose was administered under supervision by the field worker. Children were followed up for one year including an active follow-up period of 6 months with scheduled monthly home visits followed by a 6 months passive follow-up period i.e. no scheduled home visit during that period. Besides the monthly home visits, parents were advised to bring back the children to the health centres when they were sick. The research nurses team was posted at each health centre to collect all the study related information during participants’ visits.