Funding for this research was provided by:
the Swedish Research Council
the Forte Foundation
the Swedish Rheumatism Foundation
the Norrbacka-Eugenia Foundation
the Strategic Research Program in Health Care Sciences
the National Postgraduate School of Health Care Sciences
Received: 11 October 2017
Accepted: 3 January 2018
First Online: 15 March 2018
Ethics approval and consent to participate
: All participants were informed about the HEPA intervention and the assessment procedures in writing and consented by presenting themselves at the baseline assessments. The study was approved by the Regional Board of Ethics in Stockholm (2009/1509-31/1 and 2012/769-32).
: Not applicable.
: The authors declare that they have no competing interests.
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