Physical health in children with neurodevelopmental disorders.

Neurodevelopmental disorders and physical problems in the children were both based on parent telephone reports, not clinical examinations, so misclassification is possible. The neurodevelopmental disorders were identified using high cut-offs on the A-TAC, which gives higher specificity but lower sensitivity, so some children with true disorders may have been missed. Physical problems were detected with simple yes/no questions and did not specify subtypes such as epilepsy or migraine. The comparison group was made fully negative by excluding children who met even low cut-offs, so it may not represent ordinary children seen in clinics. The study population was twins, and prematurity was not corrected for, so twin or birth-related factors may influence the associations. The cancer finding involved small numbers and only living children, so it should not be treated as a stable result.

Do not conclude that neurodevelopmental disorders cause epilepsy, asthma, gut symptoms or incontinence. The study compared groups using parent-reported screening questions, did not clinically assess the children, did not adjust for prematurity, and cannot show direction or cause.