Development and Validation of the Autistic Depression Assessment Tool – Adult (ADAT-A) in Autistic Adults.

Abstract BackgroundDepression can be hard to accurately identify in autistic adults due to overlapping characteristics of autism and depression, and depression tools developed for the general population not including unique signs of depression experienced by autistic people. MethodsThree focus groups and 15 cognitive interviews with autistic adults identified response difficulties and missing autism specific items in a widely used depression assessment tool developed for the general population (PHQ-9). Feedback informed new items in the Autistic Depression Assessment Tool (ADAT-A). A further 9 cognitive interviews and two large online surveys with autistic adults refined the ADAT-A items. Subsequently, 236 autistic adults (87 male, 113 female, 33 non-binary, 18-61 years) completed the ADAT-A online, alongside self-report measures of camouflaging autistic traits (CAT-Q), Intolerance of Uncertainty (IUS-12), Suicidality (SBQ-ASC), Defeat and Entrapment (DES). Analyses explored structural validity, internal consistency, convergent and divergent validity of the ADAT-A in a community sample of autistic adults.ResultsExploratory factor analysis of the ADAT-A showed evidence in support of a three-factor solution, capturing cognitive-affective and somatic depression symptoms, and autistic specific depression symptoms. Internal consistency of each subscale and total scores were excellent (.87 - .94). The ADAT-A was significantly correlated with related constructs including self-reported suicidality, defeat and entrapment (rs>.49). The ADAT-A total score and subscales were significantly more strongly correlated with hypothesised proximally related compared to distally related constructs.LimitationsThe samples involved in the development and validation of the ADAT-A were largely female, and largely diagnosed as autistic in adulthood, which is not representative of the wider autistic population. The ADAT-A has initially been developed and validated for research purposes, and has not been validated for use in clinical contexts to screen for possible depression diagnosis.ConclusionsThe ADAT-A is a self-report autism specific depression assessment tool, developed and validated with and for autistic adults, without co-occurring intellectual disability. There is promising initial evidence in support of the measurement properties of this tool for use in research. Future research must explore whether the ADAT-A is useful in better identifying depression in autistic people in clinical settings, compared to other tools developed for the general population.