[1] Univ N Carolina, Dept Hlth Sci, Div Phys Therapy, Chapel Hill, NC USA
[2] Abilitat Childrens Therapy & Wellness Ctr, Knightdale, NC USA
[3] Univ N Carolina, Childrens Hosp, Dept Rehabil Serv, Chapel Hill, NC USA
[4] Univ Southern Calif, Div Biokinesiol & Phys Therapy, Los Angeles, CA USA
[5] Univ N Carolina, Dept Pediat, Div Neonatal Perinatal Med, Chapel Hill, NC USA
[6] Univ N Carolina, 3024 Bondurant Hall,CB7135, Chapel Hill, NC 27599 USA