Article History
Received: 28 January 2019
Accepted: 29 October 2019
First Online: 6 January 2020
Ethics approval and consent to participate
: We obtained the ethical approval for the VIP examination (Dnr 08-131 M) and the Linnaeus Database (Dnr 07. 142Ö) from the regional ethics committee in Umeå. All the VIP participants provide written consent prior to their participation in the survey.
: This manuscript does not contain any individual person’s data that needing a consent for publication.
: The authors declare that they have no competing interests.