Text and Data Mining valid from 2019-03-25
Received: 4 January 2019
Accepted: 12 March 2019
First Online: 25 March 2019
Ethics approval and consent to participate
: The ethics committee of City Clinical Hospital No. 40, Yekaterinburg, Russian Federation, approved this retrospective study (protocol number 2/09.02.2018). The permit conditions were as follows: anonymity of patient data, the results should improve the quality of care, treatment of patients should be managed according to the current guidelines, and unapproved innovative technologies should not be used for treatment of patients.
: Not applicable. This study was a retrospective study that used data obtained from medical records.
: The authors declare that they have no competing interests.
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