What distinguishes autism spectrum disorders from other developmental disorders before the age of four years?

Abstract

The increasing recognition of the benefits of early intervention for children with autism spectrum disorder (ASD) stresses the importance of early identification of children who might benefit from those programs. However, in the early years of life it may be difficult to distinguish children with ASD from children with other developmental disorders. The aim of the present study was to identify behavioural patterns that could facilitate this differentiation. Prior to diagnostic assessment, 2- and 3-year-old children (n=30), all referred to a clinic for "possible autism", were observed in a semi-structured play interaction, and their parents were interviewed about the children's early development from 0 to 24 months. Following diagnostic assessment, the 17 children fulfilling the ICD-10 criteria for ASD were compared to the 13 children diagnosed with other developmental disorders (outside the autism spectrum). On the basis of parent reports only a few distinguishing signs of ASD were found before 24 months of age. On the basis of professional observations in a semi-structured play interaction several distinguishing signs were found for the 2- and 3-year-olds; smiles in response, responds to name, follows pointing, looks to "read" faces, initiates requesting verbal and nonverbal behaviours, and functional play.

Differentiating between Autism Spectrum Disorders and Other Developmental Disabilities in Children Who Failed a Screening Instrument for ASD

“…In general, the findings indicate that when compared to children with other developmental delays (global developmental delay or developmental language delay), young children with ASD use fewer conventional gestures, especially nodding and shaking their head (Lord et al, 1993;Lord, Rutter, & Le Couteur, 1994), display more echolalia and stereotyped phrases (when speech is present) Mildenberger, Sitter, Noterdaeme, & Amorosa, 2001;Noterdaeme et al, 2000), and are less likely to initiate or respond to verbal communication (Lord, 1995;Loveland et al, 1988;Trillingsgaard et al, 2005). Toddlers with ASD and toddlers with developmental delays both have been found to have impairments in their pretend play skills (Baron Cohen et al, 1996;Charman et al, 1998).…”

“…The language, cognitive, and social differences between children with ASD and children with other delays has been examined, but the majority of this research focuses on older children and not on the behavioral differences that are seen in very young children (Adrien, Deletang, Martineau, Couturier, & Barthelemy, 2001;Bartak, Rutter, & Cox, 1977;Lord & Schopler, 1989). Few studies have focused specifically on the differential diagnosis of ASD in young children (Lord, 1995;Trillingsgaard, Sorensen, Nemec, & Jorgensen, 2005), and currently, no published studies compare the behavioral differences in toddlers with ASD and toddlers with global developmental or developmental language delay based on standardized and widely used diagnostic instruments as well as a parent-report screening measure.…”

“…In the studies comparing the social abilities and characteristics of children with ASD to those of children with other developmental delays, toddlers with ASD were found to be more impaired than children with other developmental disabilities in joint attention, imitation skills, empathic responding, pointing to express interest, interest in other children, and displaying a range of facial expressions (Charman et al, 1998;Lord, 1995;Rogers, Hepburn, Stackhouse, & Wehner, 2003;Trillingsgaard et al, 2005). Similar results have been found with slightly older children; participants with ASD were more impaired in specific aspects of social interaction, such as shared enjoyment, pointing to indicate interest, offering comfort, offering to share, eye contact, peer relationships, and overall quality of social overtures (Lord et al, 1993;Lord & Pickles, 1996;Noterdaeme, Sitter, Mildenberger, & Amorosa, 2000).…”

Assessing Communication in Autism Spectrum Disorders

“…Yet a delay in language acquisition, in and of itself, is not diagnostic of autism. Although certain interaction styles and social behaviors do discriminate between young children with ASD and children with other developmental delays, a differential diagnosis can be challenging in very young children because many children with global developmental or language delay display at least a few of the characteristic social and communicative impairments of children with ASD (Trillingsgaard, Sorensen, Nemec, & Jorgensen, 2005). In fact, up to 13%-19% of typically developing children under the age of 24 months show late language emergence, which is not associated with ASD or any developmental disorder (Zubrick, Taylor, Rice, & Slegers, 2007).…”

“…• Reduced pointing to communicate needs and express interests (Rogers, Hepburn, Stackhouse, & Wehner, 2003;Trillingsgaard et al, 2005). • Delayed development of pointing gestures, both in terms of use and responsiveness (Dawson, Meltzoff, Osterling, Rinaldi, & Brown, 1998).…”