Funding for this research was provided by:
Wroclaw Medical University (STM.C050.16.008)
Received: 15 February 2018
Accepted: 18 July 2018
First Online: 31 July 2018
Ethics approval and consent to participate
: The study was approved by the local Ethics Committee of the Wroclaw Medical University. The study was retrospective and did not require consent from the patients.
: Not applicable.
: The authors declare that they have no competing interests.
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