Psychological assessment of more able adults
with autism spectrum disorders
Adults with autism spectrum disorders (ASDs) have been identified as some of our “most vulnerable citizens” (Bryson and Autism Society of Ontario 1991, p.5). It is clear from epidemiological studies that the number of children identified with an ASD has increased in the past two decades (Tidmarsh and Volkmar 2003). However, few of these studies refer to the potential increase in the number of adults being identified. From clinical experience, it is clear that more adults are being referred for assessment and many of them are “more able” (Stoddart, Burke, and Temple 2002). A survey from the UK indicates diagnosis after the age of 16 occurred in 18% of those with autism who were “lower functioning”, 29% who were “higher functioning”, and 46% of those with Asperger Syndrome (AS) (Barnard et al. 2001).
Adults who are “more able” are the focus of this chapter. That is, those with AS, and individuals with autism or Pervasive Developmental Disorder – Not Otherwise Specified (PDD-NOS), who have mild or no intellectual disabilities (i.e. a full-scale IQ greater than 70). These individuals have problems in socialization, in communication, and in using knowledge and skills in a functional way. They may also suffer from emotional or psychological difficulties relating to their symptoms and the impact of the symptoms on their lives. This chapter will include a discussion of the reasons adults are seen for assessment, the process and product of an assessment, characteristics of importance in the assessment, and ways to examine these characteristics.
There is currently little consistency in the assessment and diagnosis of more able adults with ASDs. Therefore, while general information is drawn from the literature, much information comes from this clinician's experience in working