[1] Univ South Carolina, Arnold Sch Publ Hlth, Dept Epidemiol & Biostat, 915 Greene St Discovery 1,435C, Columbia, SC 29208 USA
[2] Univ South Carolina, South Carolina SmartState Ctr Healthcare Qual, Arnold Sch Publ Hlth, Columbia, SC 29208 USA
[3] Univ South Carolina, Rural & Minor Hlth Res Ctr, Arnold Sch Publ Hlth, Columbia, SC 29208 USA
[4] Univ South Carolina, Arnold Sch Publ Hlth, Off Study Aging, Columbia, SC 29208 USA
[5] Univ Georgia, Coll Publ Hlth, Dept Hlth Policy & Management, Athens, GA USA
[6] Univ South Carolina, Arnold Sch Publ Hlth, Hlth Serv Policy & Management, Columbia, SC 29208 USA