UC Davis

Autism screening aids in early detection and diagnosis. Several screeners are available for toddlers 16 months and older, but there is little data on the accuracy of screening measures used in the first year of life. A community sample (N = 1641) completed three screeners-M-CHAT-R, ITC, VIRSA-online at 6, 9, 12, 18, and 24 months of age (including exploratory use of M-CHAT-R prior to 16 months). At 36 months, outcomes of ASD or Non-ASD were determined by tele-evaluation and outcome surveys. Psychometric properties were assessed for all screeners at all ages, both used individually and in combination. When used in the first year of life (6-12 months), psychometric properties were in the poor range, with area under the curve (AUC) < 0.70 for all three screeners, whether used in isolation or combination. At 18 and 24 months, the M-CHAT-R and ITC outperformed the VIRSA, with psychometric properties in the fair range (AUC 0.70-0.79) used in isolation and the good range (AUC ≥ 0.80) when used in combination. Using the M-CHAT-R and ITC at more than one age in the second year also fell in the good range. This study, using procedures to address limitations of prior screening studies and follow screen-negative cases, found that none of the three screeners had adequate psychometric properties in the first year. At 18 and 24 months, findings supported the use of multiple screeners, either in combination or longitudinally, for best prediction of autism diagnosis.