Text and Data Mining valid from 2019-02-06
Received: 23 August 2017
Accepted: 26 December 2018
First Online: 6 February 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Shaoxing Women and Children’s Hospital (NO 201700189). Because of retrospective studies, we contact babies’ parents after discharge by telephone. Informed verbal consent was obtained from all participants and the ethics committee approved this procedure.
: Not applicable.
: The authors declare that they have no competing interests.
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