Funding for this research was provided by:
Text and Data Mining valid from 2018-06-11
Received: 31 March 2017
Accepted: 30 April 2018
First Online: 11 June 2018
Ethics approval and consent to participate
: Participants provided informed consent and the study was approved by the social and societal ethics committee (SMEC) of KU Leuven (G-2015 04 218).
: UEFA funded the research. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors declare no other competing interests.
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