About the Authors

Kenneth J. Scalapino

Affiliations Arthritis Section, San Francisco Veterans Affairs Medical Center, San Francisco, California, United States of America, Division of Rheumatology, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America

David I. Daikh

daikh@itsa.ucsf.edu

Affiliations Arthritis Section, San Francisco Veterans Affairs Medical Center, San Francisco, California, United States of America, Division of Rheumatology, Department of Medicine, University of California San Francisco, San Francisco, California, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: KJS DID. Performed the experiments: KJS. Analyzed the data: KJS. Wrote the paper: KJS.