Received: 28 July 2017
Accepted: 9 January 2019
First Online: 8 February 2019
Ethics approval and consent to participate
: Ethical approval for the study was granted by the institutional review boards of the Centre Médical Monkole (006 CEFA-MONKOLE/2014) in line with the principles of the Declaration of Helsinki, second revision. The aim and study procedures were explained to the parents or legal guardians and they provided written consent before any of the subjects where included.
: not applicable.
: The authors have no conflicts of interest to disclose.
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