Funding for this research was provided by:
the Foundation of the Innovation Seeding Project of the Science & Technology Department of Sichuan Province (2017062)
the Cooperative Project of Nanchong City with North Sichuan Medical College (NSMC20170461)
Text and Data Mining valid from 2018-11-29
Received: 23 August 2018
Accepted: 9 November 2018
First Online: 29 November 2018
Ethics approval and consent to participate
: This retrospective study was approved by the ethics committee of Nanchong Central Hospital and was carried out in accordance with the 1975 Helsinki Declaration. Because of the anonymous nature of the data and the opt-out option disclosed on our institution’s homepage, the requirement for additional informed consent to participate in this study was deemed unnecessary.
: Not applicable.
: The authors declare that they have no competing interests.
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