Li, Yuting
Xian, Wei
Xu, Haodi
Sun, Jinbin
Han, Bing
Liu, Hongbo http://orcid.org/0000-0002-7404-4271
Funding for this research was provided by:
the National Natural Science Foundation of Liaoning Province (no.2014021099)
Article History
Received: 21 March 2018
Accepted: 6 August 2018
First Online: 14 August 2018
Ethics approval and consent to participate
: The study was approved by the Medical Ethics Committee of China Medical University (permit number CMU6206–3008). As this was a record review study by a retrospective investigation, informed consent to participate was not required. Through informed permission from Fuxin Mining Area Social Security Administration Center the databases were accessed in this study. Confidentiality of the data was maintained, and no record of personal privacy was involved in this study.
: Not applicable.
: The authors declare that they have no competing interests.
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