Kononova, Natalia
Sikkeland, Liv Ingunn Bjoner
Mahmood, Faiza
Vistnes, Maria
Kongerud, Johny
Einvik, Gunnar
Søyseth, Vidar
Article History
Received: 1 May 2018
Accepted: 12 December 2018
First Online: 9 May 2019
Ethics approval and consent to participate
: The study protocol was approved by the Regional Medical Ethics Committee (case number 2013/1006/Regional Etisk Komite sør-øst D). All participants provided informed written consent prior to the start of the study.
: Not applicable.
: The authors declare that they have no competing interests.
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