First Online: 13 June 2019
Ethics approval and consent to participate
: This study was conducted according to the guidelines laid down in the Declaration of Helsinki and all procedures involving human subjects/patients were approved by the Research Ethics Committee of Universiti Kebangsaan Malaysia (Project Code: NN-072-2009). Written informed consent was obtained from the parents or guardians for all children. This project was registered in the Dutch Trial Registry as NTR2462.
: Not applicable.
: The authors declare that they have no competing interests. Any opinions, findings, conclusions or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of FrieslandCampina.
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