Funding for this research was provided by:
The research council of Norway
KLP - Kommunal Landspensjonskasse, Norway
Received: 26 September 2017
Accepted: 22 February 2018
First Online: 28 February 2018
Ethics approval and consent to participate
: Eligible participants were informed about the study at the day of arrival at the rehabilitation center and were given the opportunity to sign up for the study. The study was approved by the Regional Committee for Ethics in medical research (no.: 2012/1241) and all participants signed an informed consent before enrollment. The study was carried out according to the latest revision of the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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