Bubnov, Rostyslav
Polivka, Jiri Jr
Zubor, Pavol
Konieczka, Katarzyna
Golubnitschaja, Olga
Article History
Received: 17 March 2017
Accepted: 31 March 2017
First Online: 2 May 2017
Compliance with ethical standards
: All procedures performed in the current study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
: This multi-centred study has been supported by the following organisations:UnorderedList removed
: The authors declare that they have no competing interests.