Text and Data Mining valid from 2018-08-09
Received: 28 November 2017
Accepted: 21 May 2018
First Online: 9 August 2018
Ethics approval and consent to participate
: The study protocol was approved by the Heinrich-Heine University (Düsseldorf, Germany) ethics committee.
: Ausra Ramanauskaite, Kathrin Becker, Gintaras Juodzbalys, and Frank Schwarz declare that they have no competing interests.
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