The Very Early Identification of Autism: Outcome to Age 4½–5

Abstract

Forty-nine 2 years olds with social and language characteristics suggestive of autism were identified by community professionals and screening tools, then given a diagnostic assessment and reexamined at age 4 1/2. Agreement between autism clinic and screenings was high, with 88% receiving a diagnosis on the autism spectrum. The children were lower functioning relative to the autism population, thus more likely to be identified early. Reliability of diagnoses from 2 1/2 to 4 1/2 was high with 79% staying in the same diagnostic category, but more so for clear autism than for PDDNOS. About a third improved over 20 IQ points and similar number similarly declined. Changes were not related to amount or type of intervention but were related to the children's characteristics. Higher functioning children with milder autism were the most improved.

Stability and change of IQ scores in preschool children diagnosed with autistic spectrum disorder

“…We did not find higher functioning children in particular to show intellectual improvement [7,19]. Instead, IQ improved across the whole range of intellectual functioning (as measured at T1).…”

“…Few children showed a deterioration of intellectual functioning, and deterioration was not associated with any group in particular. Increase in IQ scores in children with ASD has been reported in other studies of preschool children [7,32], and children between preschool years and early adolescence [19,28].…”

“…For example, IQ has been reported to decrease between the ages of 2 and 18 years [9] whereas others have shown cognitive scores to increase between 3 and 15 years in a cross-sectional study [19] and between 2 and 13 years in a longitudinal study [28]. Eaves and Ho [7] found IQ to increase and decrease between age 2½ and 4½, in their sample of 49 children diagnosed with ASD. They found that higher functioning children were most likely to show an increase in IQ score.…”

Language outcomes of toddlers with autism spectrum disorders: a two year follow‐up

“…But a major thrust of current research has been to lower the age of identification, due in part to evidence supporting the effectiveness of early intervention [Rogers, 2006;Stahmer, Ingersoll, & Koegel, 2004]. Recent research suggests that clinical diagnosis of autism can be reliably assigned in the second year, and shows at least short-term stability [Matson, Wilkins, & Gonzales, 2008] when conferred by an team of experienced clinicians [Charman et al, 2005;Chawarska et al, 2007;Cox et al, 1999aCox et al, , 1999bEaves & Ho, 2004;Lord, 1995;Lord, Risi, & DiLavore, 2006, Stone et al, 1999aTurner, Stone, Pozdol, & Coonrod, 2006;Wetherby et al, 2004].…”

How useful are screening instruments for toddlers to predict outcome at age 4? General development, language skills, and symptom severity in children with a false positive screen for autism spectrum disorder

“…These authors do acknowledge that future research should also look at the predictive ability of screening measures and compare them. So far, studies have only looked at the diagnostic outcome years after children were screened for ASD [15,[21][22].…”