Text and Data Mining valid from 2019-01-29
Received: 2 October 2018
Accepted: 7 January 2019
First Online: 29 January 2019
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The institutional review board approved this retrospective study (Protocol number CLEA-2018-047), and the requirement to obtain informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.
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