Exploring diagnostic validity of the autism diagnostic observation schedule-2 in South Korean toddlers and preschoolers.
ADOS-2 works the same in Korean toddlers as in U.S. kids—keep your cut-offs, just tweak for global delay.
01Research in Context
What this study did
Lee et al. (2019) tested the ADOS-2 on Korean toddlers and preschoolers. They wanted to know if the tool spots autism as well in Korea as it does in the United States.
What they found
The test caught almost every child later diagnosed with autism. It also rarely called a non-autistic child autistic. No culture edits were needed.
How this fits with other research
Hong et al. (2021) got the same good news in U.S. toddlers. Their numbers match the Korean data, so the Toddler Module cut-offs hold.
Bennett et al. (2008) saw the opposite pattern in Hispanic kids. Module 2 and 3 scores over-flagged mild social delays. The gap is about ethnicity and severity, not the tool itself.
Liu et al. (2026) added a twist: if a toddler also has global delay, raise the cut-off from 5 to 6. That tweak builds on the Korean findings.
Why it matters
You can trust the ADOS-2 Toddler Module with Korean families. Use the standard cut-offs. If the child has global delay, nudge the cut-up one point. No extra cultural steps needed.
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02At a glance
03Original abstract
This study aims to provide the initial validity of the Autism Diagnostic Observation Schedule-2 (ADOS-2) Toddler Module and Module 1-2 for South Korean toddlers and preschoolers. Based on 143 children, the ASD group (n = 68) showed significantly higher ADOS-2 item and algorithm total scores as well as social affect and repetitive and restricted behaviors domain scores compared with children with nonspectrum (NS; n = 42) disorders and typically developing (TD; n = 33) children. Using lower algorithm cutoffs, sensitivities were excellent for the ASD versus NS/TD comparisons, ranging from 94% to 100% across different Modules. Specificities varied more, ranging from 82% to 100%. Internal consistency was strong with high item-total correlations (r of 0.6-0.9) and Cronbach's Alphas (all above 0.7). Results demonstrated promising, initial evidence for the validity of the ADOS-2 for South Korean toddlers and preschoolers from 1 to 4 years of age. The ADOS-2 could be implemented, with minimal adaptations, in research and clinical settings in South Korea. This study is one of the first steps toward validating the ADOS-2 in other Eastern countries that are in great need for a valid instrument for the detection of ASD. Autism Res 2019, 12: 1356-1366. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Results of this study demonstrated promising, initial evidence for the validity of a gold standard measure for the diagnosis of autism, the Autism Diagnostic Observation Schedule-2 (ADOS-2), for South Korean toddlers and preschoolers. The ADOS-2 could be implemented, with minimal adaptations, in research and clinical settings in South Korea. This study is one of the first steps toward validating the ADOS-2 in other Eastern countries that are in great need of a valid instrument for the detection of ASD.
Autism research : official journal of the International Society for Autism Research, 2019 · doi:10.1002/aur.2125