[1] Univ Michigan, Back & Pain Ctr, Dept Anesthesiol, Burlington Bldg 1,Suite 310,325 E Eisenhower Pkwy, Ann Arbor, MI 48108 USA
[2] Boston Childrens Hosp, Ctr Pain & Brain, Dept Anesthesia Crit Care & Pain Med, Boston, MA USA
[3] Boston Childrens Hosp, Dept Psychiat, Biobehav Pediat Pain Lab, Boston, MA USA
[4] Harvard Med Sch, Dept Psychiat, Boston, MA 02115 USA