[1] IWK Hlth Ctr, Ctr Pediat Pain Res, Halifax, NS B3K 6R8, Canada
[2] Dalhousie Univ, Dept Psychol, Halifax, NS, Canada
[3] Dalhousie Univ, Dept Pediat, Halifax, NS, Canada
[4] Dalhousie Univ, Dept Psychiat, Halifax, NS, Canada
[5] Dalhousie Univ, Dept Community Hlth & Epidemiol, Halifax, NS, Canada