Text and Data Mining valid from 2019-08-06
Received: 22 January 2019
Accepted: 9 July 2019
First Online: 6 August 2019
Ethics approval and consent to participate
: The study protocol was approved by The Ethics Committee of the Ministry of Health, Ibadan, Oyo State and National Health Research Ethics Committee, Abuja, Nigeria. Written informed consents were obtained from the parents/guardians of the participating children.
: Not applicable.
: The authors declare that they have no competing interests.