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Article History

Received: 1 August 2018

Accepted: 7 May 2019

First Online: 21 May 2019

Ethics approval and consent to participate

: Approval of the protocol was obtained from the Institutional Review Board of the National Institute of Health, including the use of opt-out consent; that is, parents were fully informed about all study procedures through a form attached to their questionnaire and the lack of a returned form was taken to imply consent to their child’s participation. The child’s assent was verbal.

: Not applicable.

: The authors declare that they have no competing interests.

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