Text and Data Mining valid from 2018-11-07
Received: 21 February 2018
Accepted: 25 October 2018
First Online: 7 November 2018
Ethics approval and consent to participate
: This study used the data collected in the 1st to 12th KYRBWS (2005–2016). The KYRBWS was approved by the Institutional Review Board of the Korea Centers for Disease Control and Prevention (2014-06EXP-02-P-A), and all participants and their parents or legal guardians provided informed consent to participate in the KYRBWS.
: Not applicable.
: The authors declare that they have no competing interests.
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