[1] Univ Vermont, Lamer Coll Med, Dept Med, Colchester, VT USA
[2] Univ Vermont, Lamer Coll Med, Dept Pathol & Lab Med, Colchester, VT USA
[3] Univ Alabama Birmingham, Dept Biostat, Sch Publ Hlth, Birmingham, AL 35294 USA
[4] Univ Alabama Birmingham, Sch Publ Hlth, Dept Epidemiol, Birmingham, AL 35294 USA
[5] Weill Cornell Med Coll, Div Gen Internal Med, New York, NY USA