[1] Michigan State Univ, Internal Med, E Lansing, MI 48824 USA
[2] Weill Cornell Med Coll, New York, NY USA
[3] Univ Michigan, Dept Biostat, Ann Arbor, MI 48109 USA
[4] Univ Michigan, Pulm & Crit Care Med, Ann Arbor, MI 48109 USA
[5] Oregon Rural Practice Based Res Network, Protland, OR USA
[6] Atrium Hlth, Charlotte, NC USA
[7] LA Net Community Hlth Network, Long Beach, CA USA
[8] High Plains Network, Aurora, CO USA
[9] Duke Primary Care Res Consortium, Durham, NC USA
[10] Univ Illinois, Chicago, IL USA
[11] Natl Jewish Hlth, Denver, CO USA
[12] Univ Minnesota, Blaine, MN USA
[13] Univ Kentucky, Lexington, KY USA