Hustad, Eldbjørg http://orcid.org/0000-0002-1487-0731
Skogholt, Anne Heidi
Hveem, Kristian
Aasly, Jan O.
Article History
Received: 22 May 2018
Revised: 26 June 2018
Accepted: 28 June 2018
First Online: 10 July 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interests.
: The study was approved by the Ethics Committee of Central Norway.
: Informed consent was obtained from all individual participants included in the study.