[1] Meyers Primary Care Inst, Worcester, MA USA
[2] Harvard Med Sch, Boston, MA USA
[3] Harvard Vanguard Med Associates, Boston, MA USA
[4] Kaiser Permanente Mid Atlantic States, Midatlantic Permanente Res Inst, Rockville, MD USA
[5] Henry Ford Hlth Syst, Detroit, MI USA
[6] Geisinger Hlth Syst, Danville, PA USA
[7] Henry Hood Ctr Hlth Res, Danville, PA USA
[8] Univ Penn, Sch Med, Philadelphia, PA USA
[9] Kaiser Permanente Northwest, Ctr Hlth Res, Portland, OR USA
[10] Kaiser Permanente Colorado, Colorado Springs, CO USA
[11] Natl Canc Inst, Bethesda, MD USA