Bodily and Procedural Imitation in Preschoolers at Risk for Autism

Background:
The insight in the nature of imitation problems in autism has evolved rapidly.
However, the query if these problems are general or specific remains subject of debate.

Objectives:
Present study sought to examine bodily and procedural imitation in preschoolers at risk for autism, using a standardised imitation test.

Methods:
Participants:
85 children, aged 1.9-4.5 years, taught to be autistic, and consecutively referred to University Autism Clinics in Flanders (Belgium).
A multidisciplinary clinical consensus classification (DSM-IV-TR) revealed: 68 children with Autism Spectrum Disorder (ASD) and 17 with Non-Spectrum Developmental Disorder (NS-DD).

Instrument:
Preschool Imitation and Praxis Scale (PIPS) (Vanvuchelen, Roeyers, De Weerdt).
Bodily and procedural imitation age-equivalent scores were derived from PIPS scores of 654 healthy children (1y-4.9y).
Differences between imitation age-equivalent scores and non-verbal mental age were used as criteria for imitation delays.

Results:
In children with ASD, both bodily (z=-4.0, p<0.01) and procedural (z=-2.1, p=0.03) imitation ages were significantly below the non-verbal mental age.
In contrast, in children with NS-DD, bodily (z=-1.2, p=0.21) and procedural (z=-1.4, p=0.13) imitation ages were not significantly different from the non-verbal mental age.

Conclusions:
Differences between bodily, respectively procedural imitation ages and non-verbal mental age can serve as criteria for imitation delays.
Findings suggest general imitation problems, i.e. bodily and procedural, in children with autism spectrum disorders.

References:
Vanvuchelen, Roeyers, De Weerdt, (2008) The Preschool Imitation and Praxis Scale (PIPS). Development, Reliability and Factor structure. Submitted to Psychological Assessment.