Broadband and Autism-Specific Screening Using the Early Screening for Autism and Communication Disorders (ESAC): Moving From Paper to the Smart ESAC for Children 12 to 36 Months of Age

Background: The AAP recommends that all children be screened for ASD at 18-24 months. However, there are no well-validated screening tools for ASD at this age and time needed to complete separate broadband and autism-specific tools is not feasible in primary care settings. The need for validated screening tools is critical so that families can access intensive, appropriate intervention services early.  

Objectives: The primary objectives of this study were 1) to replicate findings on the Early Screening for Autism and Communication Disorders(ESAC), a 30-item autism-specific parent-report screening tool that screens for ASD in children between 12 and 36 months of age; and 2) to develop a streamlined “smart” ESAC for primary care settings consisting of 10 broadband questions for universal screening, which if positive, are followed seamlessly by 20 autism-specific questions. 

Methods: The ESAC includes 30 recognition format or closed-choice items based on research on early red flags of ASD in all three DSM-IV domains in children 12-36 months. Florida State University and University of Michigan conducted screening from two referral sources: 1) a follow-up of over 12,000 children screened by the FIRST WORDS^® Project with the Infant-Toddler Checklist for communication delays in primary care settings; and 2) children referred for possible ASD to each university. Follow-up diagnostic evaluations were conducted for 647 children in 3 age groups: Early 2^nd year (12-17 months, m=15.38, n=203), Late 2^nd year (18-23 months, m=20.26, n=346), and 3^rd year (24-36 months, m=28.01, n=323). A best estimate diagnosis of ASD (n=283), developmental delay in which ASD was ruled out (DD; n=120), or typical development (TD; n=244) was made based on the diagnostic evaluation.  

Results: Receiver Operating Characteristic (ROC) curves run within age groups indicated excellent discrimination, and good sensitivity and specificity of established cutoffs for the ESAC 30 as an autism-specific screener in this large community and referral sample for all age groups. Item-Response Theory was used to analyze the Item Information Function and characterize performance for each item in discriminating ASD from non-ASD. In the second set of analyses, ROC curves run for each item within the three age groups indicated that slightly different item sets were needed to best discriminate children with atypical development (i.e., ASD or DD) from those with typical development. The best 10 individual items within age group demonstrated acceptable item-level sensitivity and specificity and when item sets were summed, the broadband cutoff showed good sensitivity and specificity.  

Conclusions: These results provide support for the validity of the ESAC as an autism-specific screener in children 12-36 months age and indicate that items from the ESAC can be used to develop a broadband screener. These findings offer promise for a cost-effective screener as early at 12 months of age and add to the research documenting the accuracy of parent report to screen young children, which minimizes time required of primary care providers, maximizes the role of the family, and provides reasonably accurate information about whether to refer a child for a diagnostic evaluation for ASD or other developmental problems.