Funding for this research was provided by:
National Institute of Arthritis and Musculoskeletal and Skin Diseases (2T32AR007304-36)
Arthritis Foundation (PDF 6111)
Article History
Received: 16 January 2018
Accepted: 4 April 2018
First Online: 16 April 2018
Ethics approval and consent to participate
: The University of California, San Francisco Committee on Human Research did not require review for research performed on de-identified data.
: The authors declare that they have no competing interests.
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