Autism spectrum disorders before diagnosis: results from routine developmental surveillance at 18 months

This study investigated the results from the national, routine 18-month developmental surveillance at Child Healthcare Centres (CHCs) on children later diagnosed with autism spectrum disorder (ASD).

Child Healthcare Centre records of 175 children, diagnosed with ASD before 4.5 years in Stockholm County, Sweden, were reviewed regarding the results of the eight-item neurodevelopmental surveillance. Results were contrasted with normative data from the general child population in Stockholm County.

More than one-third of the total ASD group, including half of the group with ASD and intellectual disability (ID), did not pass the required number of items, compared to one in 50 in the general child population. Of those with ASD and ID who had passed, more than one-third experienced developmental regression after 18 months of age. If the CHC surveillance had considered reported regulatory problems - crying, feeding and sleeping - then another 10% of the children with ASD and ID could have been identified during this surveillance.

The existing CHC surveillance traced half of the group of children who were later diagnosed with ASD combined with intellectual disability. Adding an item on regulatory problems to the 18-month surveillance would have increased this number by another 10%.