Ethics statement
SECONDARY
The main trial was approved by the ethics review committees of the Kilimanjaro Christian Medical University College, the London School of Hygiene & Tropical Medicine, and the Tanzanian Medical Research Coordinating Committee (NIMR/HQ/R.8a/VolIX/1803). Written informed consent from parents or guardians was obtained for each survey. Ethical clearance to perform secondary analysis was obtained from the Kilimanjaro Christian Medical University College Research and Ethics Committee, Tanzanian (No.2119). Participant’s confidentiality was maintained by ensuring the use of participant identification number during data extraction and analysis.