Poor reciprocity is a defining feature of an autism spectrum disorder (ASD). In the current study, we examined the reliability and validity of the Interactive Drawing Test (IDT), a new instrument to assess reciprocal behavior. The IDT was administered to children and adolescents with ASD (n = 131) and to a typically developing group (n = 62). The IDT had excellent inter-rater reliability and moderate to good test–retest reliability. The results showed clearly distinctive response patterns in the ASD group compared to the typically developing group, independent of verbal IQ and age. Convergent validity of the IDT was low. Sensitivity and the predictive accuracy of the IDT for detailed levels of reciprocal behavior in autism are discussed.

Differences in the social limitations of girls compared to boys on the autism spectrum are still poorly understood. Impaired social-emotional reciprocity is a core diagnostic criterion for an autism spectrum disorder. This study compares sex differences in reciprocal behaviour in children with autism spectrum disorder (32 girls, 114 boys) and in typically developing children (24 girls, 55 boys). While children with autism spectrum disorder showed clear limitations in reciprocal behaviour compared to typically developing children, sex differences were found only in the autism spectrum disorder group: girls with autism spectrum disorder had higher reciprocity scores than boys with autism spectrum disorder. However, compared to typically developing girls, girls with autism spectrum disorder showed subtle differences in reciprocal behaviour. The sex-specific response patterns in autism spectrum disorder can inform and improve the diagnostic assessment of autism in females.

Few instruments have been developed that measure impairments in reciprocity, a defining feature of autism. We introduce a new test assessing the quality of reciprocal behaviour: the interactive drawing test (IDT). Children and adolescents (n = 49) with and without high functioning autism spectrum disorders (HFASD) were invited to collaborate with an experimenter in making a joint drawing. Within both groups the performance on collaborative reciprocity improved with age. However, compared to the control group, HFASD participants showed less collaborative and more basic reciprocal behaviour and preferred to draw their own objects. They were less tolerant of the experimenter’s input as well. Performance on the IDT was independent of estimated verbal IQ. Reciprocal behaviour in self-initiated objects corresponded with more parental reported autistic traits, while reciprocal behaviour in other-initiated objects corresponded with less autistic traits. The findings of this study suggest that IDT is a promising instrument to assess reciprocity.

The assessment of autism in individuals with mild intellectual disabilities (MID) is complicated because of the overlap between autistic traits and intellectual limitations. Impaired social emotional reciprocity is a core diagnostic criterion for autism. However, it is unknown whether reciprocal behaviour differs between MID individuals with or without an autism spectrum disorder (ASD). This study explored differences in reciprocal behaviour of 35 children and adolescents with MID (intelligence quotient 50-85): 15 with ASD (ASD-MID) and 20 with typical development (TD-MID) using the Interactive Drawing Test (IDT). ASD-MID participants showed a lower quality of reciprocal behaviour compared with TD-MID participants. The difference in quality of reciprocal behaviour between ASD-MID and TD-MID participants was not significantly related with Peabody Picture Vocabulary Test scores and thus not attributable to verbal capacity. The IDT is likely to reflect the child's inclination to display reciprocal behaviour in everyday situations, as its scale scores were meaningfully associated with the level of social cognition assessed with the Social Responsiveness Scale. Thus, the IDT seems well suited for measuring impairments in reciprocal behaviour in children and adolescents with MID.