Funding for this research was provided by:
Uniwersytet Medyczny w Lodzi (502-03/6-077-01/502-64-099, 503/6-077-01/503-61-002)
Text and Data Mining valid from 2018-08-30
Received: 18 January 2018
Accepted: 20 August 2018
First Online: 30 August 2018
Ethics approval and consent to participate
: Each participant signed written informed consent, which was an obligatory requirement for the study participation. The Medical University of Lodz Ethics Committee approved this study.
: Not applicable.
: The authors declare that they have no competing interests.
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