Racial-Ethnic Comparisons of ADOS-2 Algorithms for Young Verbal Children

The current study reports comparative analyses of the ADOS-2 Module 1 (Some Words) (n = 918) and Module 2 (Phrase Speech) (n = 881) algorithmic items between Black, Hispanic, and White children aged 3-5 on data from the Study to Explore Early Development (SEED). Significant Differential Item Functioning (DIF) was identified on ADOS-2 Social Affect and Restrictive Repetitive Behavior (RRB) items from both modules, but differential test functioning (DTF) was close to zero for each subscale (range = -0.07 to 0.08). No discernible patterns were identified when comparing these results with other published studies conducted with older populations. Item level scoring differences may reflect unique study sample variance, and existing data suggests DIF is unlikely to impact scale level ADOS-2 interpretations for clinicians assessing preschool age children from different racial and ethnic backgrounds.