Text and Data Mining valid from 2018-11-19
Received: 15 March 2018
Accepted: 8 November 2018
First Online: 19 November 2018
Ethics approval and consent to participate
: Informed consent was signed by caregiver of children before the interview. The project was approved by Huaihua Women’s Federation and Municipal Commission of Health and Family Planning (No. 201563).
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.