Article History
Received: 11 March 2018
Accepted: 7 June 2018
First Online: 12 June 2018
Compliance with ethical standards
:
: S. A. I. Loggers declares that he has no conflict of interest. P. Joosse declares that he has no conflict of interest. K. J. Ponsen declares that he has no conflict of interest.
: All procedures performed in studies 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. For this type of study formal consent is not required.
: Informed consent was obtained from all individual participants included in the study.