Funding for this research was provided by:
National Institutes of Health (N/A)
Received: 13 December 2018
Accepted: 9 May 2019
First Online: 24 May 2019
Ethics approval and consent to participate
: The OAI study was approved by the Institutional Review Board of the University of California, San Francisco, and its affiliates. All participants gave written informed consent.
: Not applicable
: YW, SMH, AEW, YZL and FMC declared that they have no competing interests. JPP and JMP are shareholders in ArthroLab Inc. FA is an employee of ArthroLab Inc.
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