Funding for this research was provided by:
National Institutes of Health
Received: 21 February 2018
Accepted: 22 October 2018
First Online: 6 November 2018
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, AJT, SMH and FMC have no competing interests and are not part of the OAI investigative team. JPP, JMP and FA are not part of the OAI investigative team. JPP and JMP are shareholders in ArthroLab Inc. FA is an employee of ArthroLab Inc.
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