Text and Data Mining valid from 2018-04-02
Received: 5 September 2017
Accepted: 21 March 2018
First Online: 2 April 2018
Ethics approval and consent to participate
: The study was approved by the ethics committee of the Bavarian Medical Association (“Bayerische Landesärztekammer”) and performed in accordance with the Declaration of Helsinki. All individuals whose data were included in the analyses gave their written informed consent to participate in the study.
: Not applicable
: The authors declare that they have no competing interests.
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