Examination of the Time Between First Evaluation and First Autism Spectrum Diagnosis in a Population-based Sample

Abstract

Early identification of young children with an autism spectrum disorder (ASD) can lead to earlier entry into intervention programs that support improved developmental outcomes. The purpose of the present study was to examine identification and diagnostic patterns of children with ASD who live in a large metropolitan area. One hundred fifteen 8-year-old children diagnosed with ASD were identified from a population-based surveillance system at the Centers for Disease Control and Prevention. Primary variables of interest included earliest age of evaluation and earliest age of diagnosis identified from surveillance records, type of initial ASD diagnosis, evaluation sources that documented first ASD diagnosis, characteristics of professionals assigning first ASD diagnosis, and diagnostic tools used to aid the diagnostic process. We found that children with ASD identified by the surveillance system were initially evaluated at a mean of 48 months but were not diagnosed with ASD until a mean age of 61 months. There were no differences in timing of diagnosis based on sex or racial/ethnic classification, although degree of impairment associated with ASD predicted mean age at first evaluation and mean age at first ASD diagnosis. Most children were identified at non-school sources, such as hospitals and clinics; 24% of the sample did not receive a documented ASD diagnosis until entering school. Most practitioners (70%) did not use a diagnostic instrument when assigning the first ASD diagnosis. Implications for early identification of ASD are discussed.

The Role of the Autism Diagnostic Observation Schedule in the Assessment of Autism Spectrum Disorders in School and Community Settings

“…Independent validation of practice is also needed, in the form of record review and diagnostic confirmation of cases. For example, a recent examination of diagnostic records from 115 children diagnosed with ASD through the Metropolitan Developmental Disabilities Surveillance Program of the CDC found that professionals assigning an initial ASD diagnosis used a standardized diagnostic tool in only 30% of evaluations (Wiggins, Baio, & Rice, 2006). This stands in stark contrast to the practices reported in the present study.…”

Screening for Autism Spectrum Disorders in Flemish Day-Care Centres with the Checklist for Early Signs of Developmental Disorders

“…Harrington, Patrick, Edwards, and Brand (2006) found in their survey that ages at diagnosis ranged from 14 months to 14 years. Moreover, Wiggins, Baio, and Rice (2006) showed that the average delay between mean age at first documented evaluation and mean age at first ASD diagnosis was 13 months. In Flanders, Renty and Roeyers (2006) found an average age of 69 months at diagnosis for children younger than 12 years with an average delay of 25 months between first recognition of symptoms and diagnosis of ASD.…”

Imitation Assessment and Its Utility to the Diagnosis of Autism: Evidence from Consecutive Clinical Preschool Referrals for Suspected Autism

“…In a cohort of children younger than 12 years of age in Flanders, the Dutch-speaking region of Belgium, the average age of autism diagnosis was 5.9 years (Roeyers 2008). The long delay between parents' initial concerns and eventual diagnosis postpones appropriate intervention, which leaves parents with the sense that precious time has been lost (Wiggins et al 2006). Autism diagnosis in young children may be delayed due to doubts about diagnostic validity.…”