Text and Data Mining valid from 2018-04-19
Received: 27 October 2017
Accepted: 12 April 2018
First Online: 19 April 2018
Ethics approval and consent to participate
: The study was conducted in accordance with the Declaration of Helsinki, with approval for all sites i.e. Gothenburg, Stockholm and Linköping, from the Regional Ethics Committee at Karolinska Institute in Stockholm (2010/1121–31/3). All the participants were given written and oral information and written consent was obtained.
: The authors declare that they have no competing interests. No financial conflicts of interest are declared for any of the authors.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.