Trends in diagnostic testing practices for ASD in a population-based sample from Philadelphia County

Trends in the use of diagnostic evaluation tools are not well described, especially in high density urban areas where minority populations are typically large. Data collected for the Pennsylvania Autism and Developmental Disabilities Surveillance Program (PADDSP) of the ADDM Network will be analyzed to characterize the use of diagnostic and/or screening tests among cases of ASD in Philadelphia County over two study years, 2002 and 2006. The purpose of the presentation is to describe: the proportion of cases who received an ASD diagnostic evaluation stratified by sex and race/ethnicity for each surveillance year (2002 and 2006); and changes over time in the use of diagnostic test instruments among cases of ASD. Data include the reports of the specific ASD diagnostic tests used for children in Philadelphia County as recorded in the PADDSP database for study years 2002 and 2006. Most commonly used ASD evaluation is the CARS followed by GARS and Other. There is no difference in the use of evaluations between non-white and white males or females. Non-while males and females are more likely to have more than one evaluation. Cases from non-school as compared to school sources are twice as likely to have any ASD evaluation. Evaluations were conducted by a psychologist (49%), a developmental pediatrician (29%), other or unknown (16%), and an educator (6%).

Pending analysis of 2006 Study Year data. There was a steady increase in the proportion of children evaluated using one or more ASD diagnostic tests.