Screening for autism spectrum disorder in pediatric primary care: What is the best strategy?

Background: Two strategies have been proposed for early identification of children with autism spectrum disorders (ASD): 1) using a general screening tool followed by an ASD-specific screening tool for those who screen positive on the former; or 2) using an ASD-specific tool for all children.  The relative yield of these two strategies has not been examined. 

Objectives: This study compared the number of children identified at risk for ASD at their well child visits between the ages of 18 and 30 months using a general developmental screen tool and an autism specific screening tool.
Methods: The Parents’ Evaluation of Developmental Status (PEDS) was used as the general developmental screening tool and the Modified Checklist for Autism in Toddlers (M-CHAT) was used as the autism-specific tool. These tools were administered concurrently to 152 children.

Results: Cross tabulations and chi square tests were used to determine the utility of the PEDS as the first step of a two-part screen for ASD.  Of those who screened positive for developmental concerns on the PEDS (n = 38), 16% screened positive for ASD on the M-CHAT; of those who did not screen positive for developmental concerns on the PEDS (n = 114), 14% screened positive for ASD on the M-CHAT (p=0.79).  

Conclusions: The PEDS missed the majority of children who screened positive for ASD on the M-CHAT, suggesting that these two tools tap into very different domains of developmental concerns. The findings support the use of an ASD-specific tool for all children in conjunction with regular standardized developmental screening.