BackgroundIn this study, we revised the comprehensive autistic trait inventory (CATI)-a self-report inventory of autistic traits, in collaboration with autistic people and provided preliminary evidence for its validity as a self-report measure of autistic traits in the general population. An established strength of the CATI is its ability to capture female autistic traits. Our project aimed to extend this further, to increase the inventory's accessibility, and to minimise stigma induced by deficit-based representations of autistic experience. MethodsTogether with 22 individuals from the autism and autistic communities, we created the Revised Comprehensive Autistic Trait Inventory (CATI-R). Revisions included rewording items to increase clarity or reduce stigma and expanding items to capture diverse autistic experiences. We also present a series of guidelines for developing self-report inventories of subclinical neurodivergent traits. We validated the CATI-R within a large sample (n = 1439), comprising people with a self-reported autism diagnosis (n = 331), people who self-identified as autistic (n = 44), and non-autistic participants (n = 1046). ResultsWe successfully validated a revision of the CATI. A confirmatory factor analysis supported the six-subscale structure (two-factor bifactors model: Chi-squared = 2705.73, p < .001, RMSEA = .04, SRMR = .03, CFI = .95, TLI = .94). Spearman's rank correlations showed positive relationships between all subscales (all rs > .56, ps < .001). Convergent validity was demonstrated by significant correlations between the CATI-R and two contemporary inventories of autistic traits: the AQ (rho = .86, p < .01) and BAPQ (rho = .82, p < .01). Finally, a measurement invariance analysis indicated that total-scale scores can be compared across genders. LimitationsOur study presents only initial evidence for the validity of the CATI-R that should be enriched with further analyses and types of data, including a larger number of participants who do not identify as male or female. ConclusionsThis project provides a revised trait inventory that resonates with actual autistic experience, along with guidelines for creating self-report measures that are sensitive, accessible, and non-stigmatising. Autistic people know what it means to be autistic. So autistic people may be especially well-placed to determine how autistic traits and experiences should be measured and described. Until now, most autism questionnaires have been made by non-autistic people. In our project, autistic people-including those with and without academic research backgrounds-edited an autism questionnaire called the 'Comprehensive Autistic tTrait Inventory', or 'CATI' for short. This is a survey that requires people to read a list of statements and indicate how much each relates to their own experiences. It is used to measure the extent to which people in the general population (including those who are not autistic) have experiences associated with autism. In a large online study, we found that the edited meas-ure consistently and accurately measured autistic traits. We also propose basic guidelines for developing measures that better capture autistic people's experiences by using questions that are respectful and follow language prefer-ences of the community.
