Funding for this research was provided by:
Michigan State University
Article History
Received: 2 October 2017
Accepted: 4 April 2018
First Online: 12 April 2018
Change Date: 28 February 2022
Change Type: Correction
Change Details: A Correction to this paper has been published:
Change Details: https://0-doi-org.brum.beds.ac.uk/10.1186/s12889-022-12703-1
Ethics approval and consent to participate
: This study was approved by the ethics committee of Huainan Disease Prevention and Control Centre and Michigan State University Internal Review Board (IRB#× 15-413e), which are in accordance with the Declaration of Helsinki. Written, informed consent was obtained from participants according to these procedures prior to data collection.
: 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.