Funding for this research was provided by:
China Medical Board
Education Department of Ningxia Province (NXYLXK2017A07)
Received: 5 June 2019
Accepted: 23 December 2019
First Online: 7 January 2020
Ethics approval and consent to participate
: This study was approved by the ethical review committee of Ningxia Medical University, China (NO.2018107) and the ethical review committee of the Faculty of Medicine, Prince of Songkla University, Thailand (REC:60336181). All farmers were informed about the purpose of the study. Informed consent was obtained from each participant before the interviews.
: Not applicable.
: The authors declare that they have no competing interests.