Known-groups and convergent validity of the theory of mind task battery in children with autism spectrum disorder

Objectives: One of the most promising Theory of Mind (ToM) tests developed for children with ASD is the Theory of Mind Task Battery (ToM-TB). Still, additional psychometric properties of this tool need to be assessed. The main objective of this preregistered study was to investigate the known-groups and convergent validities of the ToM-TB compared to a well-established test used to assess ToM in children with ASD (the Strange Stories Test; SST).

Methods: A total of 68 school-aged children were recruited (34 children with ASD and 34 children with typical development). The groups were matched on sex and age, and on both receptive language abilities and overall cognitive functioning.

Results: Regarding the known-groups validity, we found group differences in the performance on the ToM-TB and SST. Additional analyses revealed that this result tended to be more robust for the ToM-TB than for the SST. Regarding convergent validity, we showed that the ToM-TB and SST correlated strongly, for children with ASD and children with typical development. In contrast, we found small correlations of these two tests with social competence in daily life. No evidence was found for greater known-groups or convergent validity of one test compared to the other.

Conclusion: Our data confirmed the relevance of the ToM-TB and the SST for the assessment of ToM in school-aged children. Future studies should continue to assess the psychometric qualities of various ToM tests to provide reliable information to best guide researchers and clinicians when choosing optimal neuropsychological tools.