[1] Univ N Carolina, Sch Med, Chapel Hill, NC 27599 USA
[2] Univ N Carolina, Cecil G Sheps Ctr Hlth Serv Res, Chapel Hill, NC 27599 USA
[3] Wake Forest Sch Med, Winston Salem, NC 27101 USA
[4] Univ Calif San Francisco, Box 1339, San Francisco, CA 94143 USA
[5] San Francisco Gen Hosp & Trauma Ctr, Ctr Vulnerable Populat Zuckerberg, San Francisco, CA USA
[6] Harvard Med Sch, Ctr Primary Care, Boston, MA 02115 USA
[7] Univ Toronto, Inst Hlth Policy Management & Evaluat, Toronto, ON, Canada
[8] Imperial Coll London, Sch Publ Hlth, London, England
[9] Univ N Carolina, 5034 Old Clin Bldg,CB 7110, Chapel Hill, NC 27599 USA
[10] Wake Forest Sch Med, Dept Internal Med, Med Ctr Blvd, Winston Salem, NC 27157 USA
[11] Wake Forest Sch Med, Dept Biostat & Data Sci, Med Ctr Blvd, Winston Salem, NC 27157 USA
[12] 635 Huntington Ave,Second Floor, Boston, MA 02115 USA