Analysis of Race and Sex Bias in the Autism Diagnostic Observation Schedule (ADOS-2).

Researchers studied whether the main autism assessment tool (ADOS-2) works fairly for children of different races and genders. They looked at over 6,000 children and found some items on the test worked differently for Black children versus White children, and for girls versus boys. Most problems were with social skills items being harder to score for Black children. However, these differences didn't greatly affect overall diagnosis results, suggesting the test is generally fair but some areas need attention.

This cross-sectional study examined potential bias in the ADOS-2 autism diagnostic tool across race and sex using data from 6,269 children evaluated for ASD. Researchers analyzed differential item functioning (DIF) to identify measurement biases. Results showed 16 of 140 diagnostic items (11%) had significant DIF - 8 items showed racial bias (mostly affecting social affect items) and 5 items showed sex bias. Most biased items were more difficult for Black/African American children compared to White children.

Hand mannerisms showed consistent bias across modules for females. However, the overall effect of these biases on total diagnostic outcomes was not large, suggesting the ADOS-2 does not have widespread systematic measurement bias.

Clinicians should be aware of potential bias in specific ADOS-2 items, particularly social affect items when assessing Black/African American children and hand mannerisms when assessing females. These findings support the need for culturally sensitive diagnostic approaches and may inform future ADOS-2 revisions to reduce measurement bias.

Single-site study from Mid-Atlantic US region limits generalizability. Cross-sectional design cannot establish causation. Study focused only on Black/African American versus White children, excluding other racial/ethnic groups. Sample was predominantly male (79.4%), potentially limiting sex bias analysis power.

There are long-standing disparities in the prevalence of autism spectrum disorder (ASD) across race and sex. Surprisingly, few studies have examined whether these disparities arise partially out of systematic biases in the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2), the reference standard measure of ASD. To examine differential item functioning (DIF) of ADOS-2 items across sex and race. This is a cross-sectional study of children who were evaluated for ASD between 2014 and 2020 at a specialty outpatient clinic located in the Mid-Atlantic region of the US.

Data were analyzed from July 2021 to February 2022. Child race (Black/African American vs White) and sex (female vs male). Item-level biases across ADOS-2 harmonized algorithm items, including social affect (SA; 10 items) and repetitive/restricted behaviors (RRBs; 4 items), were evaluated across 3 modules. Measurement bias was identified by examining DIF and differential test functioning (DTF), within a graded response, item response theory framework.

Statistical significance was determined by a likelihood ratio χ2 test, and a series of metrics was used to examine the magnitude of DIF and DTF. A total of 6269 children (mean [SD] age, 6.77 [3.27] years; 1619 Black/African American [25.9%], 3151 White [50.3%], and 4970 male [79.4%]), were included in this study. Overall, 16 of 140 ADOS-2 diagnostic items (11%) had a significant DIF. For race, 8 items had a significant DIF, 6 of which involved SA.

No single item showed DIF consistently across all modules. Most items with DIF had greater difficulty and poorer discrimination in Black/African American children compared with White children. For sex, 5 items showed significant DIF. DIF was split across SA and RRB.

However, hand mannerisms evidenced DIF across all 5 algorithms, with generally greater difficulty. The magnitude of DIF was only moderate to large for 2 items: hand mannerisms (among female children) and repetitive interests (among Black/African American children). The overall estimated effect of DIF on total DTF was not large. These findings suggest that the ADOS-2 does not have widespread systematic measurement bias across race or sex.

However, the findings raise some concerns around underdetection that warrant further research.