Funding for this research was provided by:
Forskningsrådet om Hälsa, Arbetsliv och Välfärd (2009–1761)
National Institute of Arthritis and Musculoskeletal and Skin Diseases (AR056019)
Received: 12 January 2017
Accepted: 24 July 2017
First Online: 12 September 2017
Ethics approval and consent to participate
: Not applicable. This is a systematic review of previously published studies.
: Not applicable.
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