Text and Data Mining valid from 2018-04-05
Received: 18 January 2016
Accepted: 20 March 2018
First Online: 5 April 2018
Ethics approval and consent to participate
: The study was approved by the Institutional Review Board of the School of Public Health, Tongji Medical College of Huazhong University of Science and Technology (IRB Approval File No. 09), and the Scientific Committee for study protocols validation of the Faculty of Health Sciences (FACSS) of the University of Bangui (No 2070 / UB / FACSS / CSCVPER / 16). Patient consent was not required due to the retrospective nature of this study.
: No applicable.
: The authors declare that they have no competing interests.
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