[1] Univ Hosp Southern Denmark, Lillebaelt Hosp, Dept Pediat & Adolescent Med, Kolding, Denmark
[2] Univ Sydney, Sydney Med Sch, Cerebral Palsy Alliance Res Inst, Fac Med & Hlth,Special Child & Adolescent Hlth, Sydney, NSW, Australia
[3] Univ Zagreb, Childrens Hosp Zagreb, Ctr Excellence Reprod & Regenerat Med, Med Sch, Zagreb, Croatia
[4] Natl Hlth Inst Dr Richardo Jorge, Dept Epidemiol, Natl Registry Congenital Anomalies, Lisbon, Portugal
[5] Univ Zagreb, Childrens Hosp, Med Sch, Zagreb, Croatia
[6] Womens & Childrens Hosp, South Australian Birth Defects Register, Womens & Childrens Hlth Network, Adelaide, SA, Australia
[7] Western Australian Register Dev Anomalies, Dept Hlth Western Australia, Perth, Australia
[8] Univ Western Australia, Telethon Kids Inst, Perth, WA, Australia
[9] Univ Hosp Rigshospitalet, Univ Copenhagen, Dept Pediat, Copenhagen, Denmark
[10] Univ Copenhagen, Dept Clin Med, Copenhagen, Denmark
[11] Vestfold Hosp Trust, Norwegian Qual & Surveillance Registry Cerebral Pa, Tonsberg, Norway
[12] Univ Bergen, Dept Global Publ Hlth & Primary Care, Bergen, Norway
[13] Norwegian Inst Publ Hlth, Div Mental & Phys Hlth, Bergen, Norway
[14] Natl Hlth Inst Dr Richardo Jorge, Dept Epidemiol, Natl Registry Surveillance Cerebral Palsy, Lisbon, Portugal
[15] Childrens Hosp Westmead, Grace Ctr Newborn Intens Care, Sydney, Australia