The prevalence of autism spectrum disorder (ASD) has increased from 1 in 150 children in the 2000 to 1 in 68 in the 2010.4 It is unclear if this increase is attributable to a true increase in numbers, or due to a broader definition and better diagnosis. Likely, it is a combination of factors. The prevalence of AS is not well established, but some studies have reported a figure of 1 in 300.5 AS has no racial predominance, but is more common in males than females with a ratio of 4:1.
A diagnosis of ASD also has significant economic implications. Caring for a child with ASD costs at least $17,000 more per year compared to a child without the disorder. Costs include health care, education, ASD-related therapy, family-coordinated services, and caregiver time. It is estimated that total societal costs of caring for children with ASD were over $9 billion in 2011.6
Standard childhood surveillance surveys are recommended by the American Academy of Pediatrics to identify developmental delays in children. In particular, all children should be screened for ASD during well baby visits at 18 and 24 months.7 Children who are suspected to have ASD should receive further evaluation.
A key change in DSM-5 is that the diagnostic categories of autistic disorder, Asperger’s and pervasive developmental disorder (PDD-NOS) have been replaced by a single umbrella term, autism spectrum disorder. A workgroup suggested that the DSM-5 definition was more accurately reflective of the current knowledge of autism. Furthermore, separation of ASD from normal developmental is reliable, but differentiation between disorders within the spectrum (PDD-NOS vs. Asperger’s) is not.
ASD is classified along the same lines and includes deficits in social communication and restricted, repetitive patterns of behavior, interest and activities. However, the criteria are somewhat more stringent since more symptoms are needed to satisfy the criterion for fixated interests and repetitive behaviors. Furthermore, delay in language development is no longer necessary for the diagnosis. Other distinctions are made based on severity levels depending on level of support an individual needs as a result of the deficits.