[1] Univ Minnesota, Sch Publ Hlth, Div Hlth Policy & Management, 420 Delaware St SE,MMC 729, Minneapolis, MN 55455 USA
[2] Univ Minnesota, Sch Publ Hlth, Div Biostat, Minneapolis, MN 55455 USA
[3] Hennepin Cty Med Ctr, Analyt Ctr Excellence, Minneapolis, MN 55415 USA
[4] Hennepin Cty Med Ctr, Div Infect Dis, Minneapolis, MN 55415 USA