[1] Queens Univ, Dept Publ Hlth Sci, Kingston, ON K7L 3N6, Canada
[2] ASD CARC, Kingston, ON K7M 8A6, Canada
[3] Ongwanada Resource Ctr, Kingston, ON K7M 8A6, Canada
[4] Dept Educ & Early Childhood Dev, Summerside, PE C1N 1B6, Canada
[5] Dept Hlth & Community Serv, St John, NF A1B 4J6, Canada
[6] Univ British Columbia, Dept Med Genet, Vancouver, BC V6H 3N1, Canada
[7] Univ British Columbia, Childrens & Womens Hlth Ctr BC, Vancouver, BC V6H 3N1, Canada
[8] Univ Calgary, Dept Pediat, Calgary, AB T2N 4Z6, Canada
[9] Univ Calgary, Dept Community Hlth Sci, Calgary, AB T2N 4Z6, Canada
[10] Alberta Childrens Prov Gen Hosp, Behav Res Unit, Calgary, AB T3B 6A8, Canada
[11] Univ Calgary, Dept Med Genet, Calgary, AB T2N 4N1, Canada
[12] Queens Univ, Dept Community Hlth & Epidemiol, Kingston, ON K7L 3N6, Canada