[1] Univ Vermont, Dept Family Med, Burlington, VT 05401 USA
[2] Univ Vermont, Dept Radiol, Burlington, VT 05401 USA
[3] Grp Hlth Res Inst, Seattle, WA USA
[4] Oregon Hlth & Sci Univ, Dept Family Med, Portland, OR 97201 USA
[5] Univ Calif San Francisco, Dept Radiol, San Francisco, CA USA
[6] Amer Canc Soc, Dept Canc Control Sci, Atlanta, GA 30329 USA
[7] Washington Univ, Sch Med, Dept Radiol, St Louis, MO 63110 USA
[8] Univ Calif Los Angeles, Dept Radiol, Los Angeles, CA USA
[9] Grp Hlth Cooperat Puget Sound, Seattle, WA USA
[10] Univ Calif San Francisco, Dept Med, San Francisco, CA USA
[11] Univ Calif San Francisco, Dept Epidemiol & Biostat, San Francisco, CA USA
[12] Dartmouth Coll, Dept Community & Family Med, Lebanon, NH 03756 USA
[13] Univ N Carolina, Dept Radiol, Chapel Hill, NC USA
[14] Harvard Univ, Dept Biostat, Boston, MA 02115 USA
[15] Univ New Mexico, Dept Internal Med, Albuquerque, NM 87131 USA
[16] Coventry & Warwickshire Hosp, Breast Screening Unit, Coventry CV1 4FH, W Midlands, England
[17] Univ Calif Davis, Sch Med, Dept Publ Hlth Sci, Davis, CA USA