Published on in Vol 6, No 2 (2018): Apr-Jun
                                    Preprints (earlier versions) of this paper are
                                    available at
                                    https://preprints.jmir.org/preprint/8687, first published
                                    .
                                

1 Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, CA, United States
2 VA Medical Center, San Francisco, CA, United States
