Funding for this research was provided by:
Qingdao Diabetes Prevention Program and World Diabetes Foundation (WDF07-308, WDF05-108)
Text and Data Mining valid from 2018-04-03
Received: 16 October 2017
Accepted: 8 March 2018
First Online: 3 April 2018
Ethics and consent to participate
: All the participants voluntarily signed the informed consent before their participation and the consent of ethics, including three urban districts (Shinan, Shibei and Sifang) and three rural districts (Huangdao, Jiaonan, Jimo), was obtained from ethics committee in Qingdao Municipal Center for Disease Control and Prevention. This study was approved by the local ethics committee at Qingdao Municipal Health and Family planning commission.
: Not applicable.
: The authors declare that they have no competing interests.
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