Fig. 2.

Receiver operating characteristic (ROC) curves for the Social Communication Questionnaire (SCQ): autism spectrum disorder (ASD) with phrase speech at 36 months.

(a) SCQ total (manual score), area under ROC curve 0.71 (95% CI 0.68–0.74); (b) SCQ communication score, area under ROC curve 0.65 (95% CI 0.62–0.68); ; (c) SCQ social interaction score, area under ROC curve 0.71 (95% CI 0.68–0.74); (d) SCQ repetitive behaviour score, area under ROC curve 0.62 (95% CI 0.58–0.65). Includes all responders to the Norwegian Mother and Child Cohort (MoBa) 36-month questionnaire (n = 58 520). The sample includes 385 individuals with ASD: 86 without phrase speech at 36 months, 294 with phrase speech at 36 months and 5 with missing information about phrase speech. For children with ASD with phrase speech, the communication score (b) includes the 13 communication items (items 2–6, 20–25, 34–35). The social interaction score (c) includes the 15 social interaction items (items 9–10, 19, 26–33, 36–37, 39–40). The repetitive behaviour score (d) includes the eight repetitive behaviour items (items 7–8, 11–16).