Validation of Indiana's Early Evaluation Hub System

Eye-tracking data will be collected using a commercially-available remote eye-tracking system (Eyelink Portable Duo). Eye movements and pupil diameter will be collected while participants view a series of developmentally appropriate pictures and movies. The eye-tracker consists of two cameras; one that monitors eye movements and a second scene camera that monitors head movements, which permits eye tracking to take place without any equipment touching the child. Children will be asked to sit in highchair or on a caregiver's lap and will face a computer monitor. After a sticker is applied to the child's forehead and brief eye-movement calibration completed, next visual stimuli (i.e., pictures and videos) will be presented on a laptop computer monitor that is placed at approximately 60-80cm from the child. The eye tracking portion of the visit will last approximately 15 minutes or until the child is no longer able to attend to pictures/videos.

A Classification and Regression Tree (CART) Analysis, based on recursive partitioning, was used to determine which combination of variables (EE Hub PCP diagnosis, diagnostic certainty, composite biomarker, and biomarker frequency \[sum of all individual biomarkers (0-6) that exceeded the 95% specificity threshold for each child\]) best predicted reference standard autism diagnosis.