[1] Univ N Carolina, Natl Ctr Catastroph Sport Injury Res, Chapel Hill, NC USA
[2] Univ N Carolina, Gillings Sch Global Publ Hlth, Dept Epidemiol, Chapel Hill, NC USA
[3] Univ N Carolina, Dept Exercise & Sport Sci, Chapel Hill, NC USA
[4] Univ N Carolina, Injury Prevent Res Ctr, Chapel Hill, NC USA
[5] Univ N Carolina, Matthew Gfeller Sport Related TBI Res Ctr, Chapel Hill, NC USA
[6] Emerson Hosp, Concord, CA USA
[7] Boston Univ, Boston, MA USA