Qiao, Yuting
Di, Jiangli
Yin, Lina
Huang, Aiqun
Zhao, Wei
Hu, Huanqing
Chen, Sidi
Article History
Received: 8 October 2023
Accepted: 15 April 2024
First Online: 22 April 2024
Declarations
:
: The study was approved and exempt from informed consent by the Ethics Committee of the National Center for Women and Children’s Health, Chinese Center for Disease Control and Prevention (No.FY2015–007 & No.FY2022-05). It is confirmed that all methods were performed in accordance with the relevant guidelines and regulations. The informed consent forms were waived because that all the information in the study was collected from Maternal and Child Care Handbook written by doctors in place of collecting data face-to-face with the subjects, and the data we used was lack of identification of individuals.
: Not applicable.
: The authors declare that they have no competing interests.