[1] Univ N Carolina, Div Comprehens Oral Hlth Periodontol, Adams Sch Dent, Chapel Hill, NC 27515 USA
[2] Univ N Carolina, Div Oral & Craniofacial Hlth Sci, Adams Sch Dent, Chapel Hill, NC 27515 USA
[3] Univ South Carolina, Sch Med, Dept Neurol, Columbia, SC 29208 USA
[4] Univ N Carolina, Gillings Sch Global Publ Hlth, Dept Biostat, Chapel Hill, NC 27515 USA
[5] Univ Minnesota, Sch Publ Hlth, Div Epidemiol & Community Hlth, Minneapolis, MN USA