Background: Diagnosis of ASD requires systematic and structured observation of a child by trained clinicians. While the diagnostic process is comprehensive, the first step is a screening – known as the Modified Checklist for Autism in Toddlers (M-CHAT) – that takes place at children’s regular pediatric appointments when they are 18 months old.

What’s New: A recent study focused on children whose M-CHAT screenings were negative, but who later received ASD diagnoses. The researchers examined data from more than 68,000 children collected as part of the Norwegian Mother and Child Cohort Study to look for children who passed the screening at 18 months but later received a diagnosis of ASD.

The researchers found:

• 228 of the children who screened negative ultimately received ASD diagnoses, constituting “false negatives.”

• Both boys and girls in the false negative group were rated as less social, less communicative, and having diminished gross motor skills compared to their counterparts in the true negative group. These effects were larger among girls, who constituted 16 percent of false negatives.

• Boys and girls in the false negative group were also shown to have diminished fine motor skills and to be less sociable than their counterparts in the true negative group.

• While boys in the false negative group were more shy than boys in the true negative group, the opposite was true of girls.

• No difference was found between the false and true negative groups in terms of emotionality and activity.

Why it’s important: This is the first study to establish a profile of “false negatives” for the M-CHAT screening. Future research

Modified Checklist for Autism in Toddlers (M-CHAT)

Source(s) :