[1] Univ Rochester, Family Med, Oncol, Rochester, NY 14620 USA
[2] Univ Rochester, Ctr Community Hlth, Rochester, NY 14620 USA
[3] Univ Colorado, Sch Med, Family Med, Denver, CO USA
[4] Univ Calif San Francisco, Family & Community Med, San Francisco, CA 94143 USA
[5] Case Western Reserve Univ, Family Med Epidemiol & Biostat Sociol & Oncol, Cleveland, OH 44106 USA