Funding for this research was provided by:
National Natural Science Foundation of China (71673169)
Text and Data Mining valid from 2018-07-23
Received: 12 December 2017
Accepted: 2 July 2018
First Online: 23 July 2018
: Lina Su (1990 -), female, research direction: social medicine and health management.Long Sun (1985-), male, research direction: suicide and social medicine.Correspondent: Lingzhong Xu (1964-), male, research direction: health care management and health economy.
: This article is a review and doesn’t involve animals and personal information survey, so the ethics approval and consent to participate are not applicable.
: This review doesn’t contains any individual person’s data, so the consent for publication is applicable.
: All the authors declare that they have no competing interests.