Funding for this research was provided by:
National Institute on Aging (T35AG038047)
Rheumatology Research Foundation (MSRP)
National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR067743, R01AR067743-02S1, P60AR064166, P60AR049465)
Centers for Disease Control and Prevention (U01DP006266)
Received: 27 August 2018
Accepted: 28 March 2019
First Online: 11 April 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Boards of the University of North Carolina at Chapel Hill and the Centers for Disease Control and Prevention. All participants gave written informed consent at the time of recruitment and each research clinic visit assessment.
: Not applicable.
: Dr. Amanda Nelson is a member of the Editorial Board of <i>BMC Musculoskeletal Disorders</i>. Otherwise, the authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.