Article History
Received: 25 September 2018
Accepted: 22 November 2018
First Online: 30 November 2018
Compliance with ethical standards
:
: The study was approved by the ethics committee of the Medical Association Saxony-Anhalt (no. 7/15). All participants got pertinent information and gave their permission to be part of a study. All participants gave informed and written consent.
: The data sets used and analysed during the current study available from the corresponding author on reasonable request.
: All authors declare that they have no competing interests.