[1] Univ Massachusetts, Sch Med, Meyers Primary Care Inst, Fallon Fdn, Worcester, MA 01605 USA
[2] Kaiser Permanente, Denver, CO USA
[3] Harvard Univ, Sch Med, Dept Ambulatory Care & Prevent, Boston, MA USA
[4] Harvard Pilgrim Hlth Care, Boston, MA USA
[5] Grp Hlth Cooperat Puget Sound, Ctr Hlth Studies, Seattle, WA 98101 USA
[6] HealthPartners Res Fdn, Minneapolis, MN USA
[7] Kaiser Permanente, Atlanta, GA USA
[8] Kaiser Permanente NW, Portland, OR USA
[9] US FDA, Off Surveillance & Epidemiol, Ctr Drug Evaluat & Res, Silver Spring, MD USA
[10] US FDA, Off Womens Hlth, Rockville, MD 20857 USA