Article History
Received: 7 November 2016
Accepted: 23 May 2018
First Online: 4 June 2018
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of the Ärztekammer des Saarlandes, Saarbrücken (ID number 58/09). All subjects (≥ 18 years) were fully informed about the study objectives and methods and gave their written informed consent before participating in this non-randomized controlled pilot trial.
: The authors declare that they have no competing interests.
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