Funding for this research was provided by:
EuroQol Research Foundation (2014160)
Text and Data Mining valid from 2019-02-09
Accepted: 14 January 2019
First Online: 9 February 2019
Compliance with ethical standards
: All authors, except Miguel A. Perez-Sousa, are members of the EuroQol Group.
: All procedures performed in studies involving human participants were in accordance with the ethical standard of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. For this study, ethical approval was obtained from an ethics committee in each country.
: Informed consent was obtained from all individual participants (in the context of this study from the parents of the participating children and adolescents) included in the study.