Received: 11 March 2019
Accepted: 11 June 2019
First Online: 18 June 2019
Compliance with ethical standards
: Zafra Cooper declares that she has no conflict of interest.Simona Calugi declares that she has no conflict of interest.Riccardo Dalle Grave declares that he has no conflict of interest.
: All studies referred to and previously published by the authors involving human participants were in accordance with the ethical standards of the relevant institutional committees and with the 1964 Helsinki Declaration and its later amendments.
: Informed consent was obtained from all participants.