Frequently Asked Questions

Where can I find detailed information about the CATI?

The manuscript outlining the development and validation of the CATI is published as an Open Access article in Molecular Autism, which is accessible at: https://doi.org/10.1186/s13229-021-00445-7.

If I use the CATI, how should I cite it?

English, MCW, Gignac, GE, Visser, TAW, Whitehouse, AJO, Enns, JT, & Maybery, MT. (2021). The Comprehensive Autistic Trait Inventory (CATI): development and validation of a new measure of autistic traits in the general population. Molecular Autism, 12(37). https://doi.org/10.1186/s13229-021-00445-7.

Why was the CATI created?

While other broad measures of autistic traits have existed for some time now, such as the Autism Spectrum Quotient (Baron-Cohen et al., 2001) and the Social Responsiveness Scale (SRS-2; Constantino et al., 2003), our understanding and conceptualisation of autism has changed considerably since their initial development. For example, sensory sensitivity is a relatively recent addition to autism diagnostic criteria, and items addressing this area are largely absent from older measures of autistic traits.

Though new measures have been created to fill gaps in older broad measures of autistic traits (e.g. Glasgow Sensory Questionnaire; Robertson and Simmons, 2013), there are inefficiencies in adminstering multiple questionnaires to cover the wide spectrum of autistic traits as the scales often differ in response options, item phrasing, and scoring methods. Consequently, there is a need for a modern, broad measure of autistic traits that can resolve these issues.

What can the CATI be used for?

The CATI was primarily developed for use in research contexts where researchers are interested in quantifying autistic traits, either broadly or specific in nature, within members of the general population.

Currently, it is NOT clinically-validated for use in diagnoses and cannot and should not be used as an assessment tool for diagnosing autism.

How was the CATI developed?

Initial development of the CATI followed consideration of current diagnostic criteria, as well as autistic traits and behaviours that were of emerging interest in the literature (e.g. camouflaging). The initial pool of potential items was developed following several rounds of consultation with researchers and clinicians who were personal contacts of the authors. Further refinement of the prospective items was achieved through consultations with autistic adults who were members of the UWA Peer Mentor Support group.

Eventually, 107 pilot items had been created. These items were administered to 1256 members of the general population using the online research platform, Prolific Academic. Responses were then subject to exploratory factor analysis, with the results suggesting the presence of six subscales. Seven items were selected from each subscale to create the 42-item CATI. This version of the CATI was then completed by another 1145 participants, and confirmatory factor analysis of their responses verified the psychometric adequacy of a 42-item, six-subscale measure.

Has the CATI been assessed for reliability and validity?

Confirmatory factor analysis (in a separate participant sample) indicated that the six-subscale structure of the CATI was a good fit for the data. Cronbach alpha (reliability) for the total-scale score was found to be excellent (.95), while the reliability of the subscales was also high (.81-.94). Reliabilities typically exceeded those found for the Autism-Spectrum Quotient (Baron-Cohen et al., 2001) and Broad Autism Phenotype Questionnaire (Hurley et al., 2007), which were also completed by participants.

A third study (n = 195) examined the validity of the CATI subscales by comparing the subscale scores to those obtained from existing validated measures, including the Autism Spectrum Quotient (Baron-Cohen et al., 2001), Adult Repetitive Behaviour Questionnaire (RBQ-2A; Barrett et al., 2015), Camouflaging Autistic Trait Questionnaire (Hull et al., 2019) and Glasgow Sensory Questionnaire (Robertson and Simmons, 2013). Each CATI subscale correlated strongly (>.68) with each comparison measure, and was often more reliable than the comparison measure despite having fewer items.

Can I modify the CATI?

The CATI was developed and it's psychometric properties examined in a controlled, consistent manner. Modifying the CATI (i.e. order or phrasing of items, changing the response scale, etc) may alter the psychometric properties and is therefore discouraged. Please contact us before making any modifications, including translations.

If it is necessary to 're-create' the CATI (e.g. for adminstration in your survey software), please be careful not to introduce any accidental changes or modifications.

I got a high score on the CATI. Am I autistic?

First, it is important to note that the CATI has not been clinically validated for identifying autism. Autism is a complex condition that can present in a multitude of ways, and thus should be assessed by qualified clinicians. Furthermore, autistic traits are known to overlap with traits and behaviours seen in other conditions, such as anxiety and eating disorders. It is currently unknown how well the CATI can distinguish between autism and other clinical conditions and, consequently, a high CATI score might reflect something other than autism. If your score is causing you concern, you should speak about it with your GP.

The following is preliminary and remains to be confirmed with a larger clinical sample! Based on the self-reported responses of 56 autistic and 1076 non-autistic participants in the second study of our development and validation paper, we identified a total-scale score of 134 to be the optimum threshold for classification. Roughly 80% of non-autistic individuals had total-scale scores below this value, and roughly 80% of autistic individuals had total-scale scores about it. Data from 77 non-diagnosed but self-identifying autistic individuals closely matched the trend seen for diagnosed autistic individuals.

I have feedback. Where should I send it?

Feedback of any kind would be valuable in assisting us to further develop and validate the CATI! If you have questions, suggestions or feedback, please send an email to michael.english@uwa.edu.au.