[1] Columbia Univ, Sch Publ Hlth, Columbia Coll Phys & Surg, Div Gen Med, New York, NY USA
[2] Columbia Univ, Sch Publ Hlth, Div Epidemiol, New York, NY USA
[3] Johns Hopkins Univ, Sch Hyg & Publ Hlth, Dept Epidemiol, Baltimore, MD USA
[4] West Virginia Univ, Inst Occupat & Environm Hlth, Morgantown, WV USA
[5] West Virginia Univ, Prevent Res Ctr, Morgantown, WV USA
[6] Univ North Carolina Chapel Hill, Sch Publ Hlth, Dept Epidemiol, Chapel Hill, NC USA
[7] Univ Minnesota, Sch Publ Hlth, Div Epidemiol, Minneapolis, MN 55455 USA
[8] NHLBI, Div Epidemiol & Clin Applicat, NIH, Bethesda, MD 20892 USA
[9] Univ Mississippi, Med Ctr, Dept Prevent Med, Div Epidemiol, Jackson, MS 39216 USA