[1] Univ Kansas, Med Ctr, Dept Prevent Med & Publ Hlth, MS 1008,3901 Rainbow Blvd, Kansas City, KS 66160 USA
[2] Univ Kansas, Med Ctr, Ctr Amer Indian Community Hlth, Kansas City, KS 66103 USA
[3] Univ Oklahoma, Hlth Sci Ctr, Dept Biostat & Epidemiol, Oklahoma City, OK USA
[4] Brown Univ, Sch Publ Hlth, Providence, RI 02912 USA
[5] Univ Kansas, Med Ctr, Dept Biostat, Kansas City, KS 66103 USA
[6] Univ Kansas, Med Ctr, Dept Family Med, Kansas City, KS 66103 USA
[7] Amer Indian Hlth Res & Educ Alliance Inc, Kansas City, KS USA