Identifying and Diagnosing Autism Spectrum Disorder in Cognitively and Verbally Able Adults: An Exploratory Vignette-Based Study of Clinicians’ Judgment, Experience & Perspectives

Background: Despite recent improvements in identifying Autism Spectrum Disorder (ASD) across age and ability level, there remains a potentially large number of cognitively and verbally able adults with an unidentified ASD who are either undiagnosed or misdiagnosed due to challenges experienced by professionals in appropriate, timely and valid identification and diagnosis.

Objectives: To date and to our knowledge, no published studies have examined the factors influencing the likelihood that an ASD diagnosis will be considered by general mental health professionals in adult clients, nor the experiences and perspectives of these professionals. The present study aimed to utilize a vignette diagnostic activity to investigate the thinking and decision-making process of identifying possible ASD in cognitively and verbally able adults by clinicians and clinicians-in-training. Research in this area could help to improve identification and diagnosis of ASD of undiagnosed adults in general adult mental health settings and in professional training.

Methods: Using a mixed methods design comprising a quantitative survey (n=21) and qualitative focus groups (n=5), this study examined the client- and clinician-related factors influencing clinicians and clinicians-in-training in considering a possible ASD diagnosis in three case vignettes of adults with ASD. Participants’ experiences with and perspectives regarding the identification of ASD in adults were also explored.

Results: ASD was considered as a diagnostic possibility only 22% of the time in the vignette activity. Factors that prompted a consideration of ASD fell into four themes: 1) impairments in social communication and interaction; 2) restricted, repetitive patterns of behaviour, interests, or activities; 3) history and pervasiveness of difficulties; and 4) family history of ASD. Even though more recently trained professionals were more likely to consider an ASD diagnosis, most participants reported several challenges and concerns faced in the identification of adults with suspected ASD.

Conclusions: Results suggest several specific areas for training of general mental health professionals in order to improve the overall identification and diagnostic process for adults with a suspected ASD.