Funding for this research was provided by:
Foundation of Shanghai Municipal Commission of Health and Family Planning (201440037)
Article History
Received: 28 April 2018
Accepted: 13 March 2019
First Online: 20 March 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the XinHua hospital, and conformed to the tenets of the Declaration of Helsinki. Each patient’s guardian or parents signed a consent form.
: We confirm that all participants’ parents/legal guardians in our study have given their written consents for the medical information to be published. A copy of the written consent is available for review by the editor of this Journal.
: The authors declare that they have no competing interests.
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