Assessment & Research

The autism diagnostic observation schedule-generic: a standard measure of social and communication deficits associated with the spectrum of autism.

Lord et al. (2000) · Journal of autism and developmental disorders 2000
★ The Verdict

The 2000 ADOS-G launched a reliable 30-minute autism test, but later revised algorithms and module tweaks give sharper answers today.

✓ Read this if BCBAs who conduct or supervise autism evaluations in clinics or schools.
✗ Skip if RBTs who only run skill-acquisition programs and never give diagnostic tests.

01Research in Context

01

What this study did

Pilgrim et al. (2000) built the first generic version of the Autism Diagnostic Observation Schedule. They call it ADOS-G.

The team wanted one short, play-based test that any trained clinician could use. It takes about 30 minutes.

02

What they found

The new ADOS-G gave the same autism diagnosis no matter who gave the test. It also separated autism from non-spectrum disorders with high accuracy.

The tool worked for kids, teens, and adults with different language levels.

03

How this fits with other research

Gotham et al. (2007) later merged two scoring areas and created the 'revised algorithm.' It replaced the 2000 version because it raised diagnostic accuracy.

Oosterling et al. (2010) repeated the 2007 study in a new sample and confirmed the revised algorithm still wins, especially for older or verbal children.

Fleury et al. (2018) pooled eight studies and found mixed numbers. They warn that ADOS-2 is not always better than the original ADOS-G. The difference depends on the child’s age and language level, so check which algorithm you use before trusting the cut-off score.

04

Why it matters

If your clinic still owns 1990s ADOS-G kits, upgrade to the revised or ADOS-2 algorithms for clearer scores. For toddlers with global delay, raise the cut-off by one point. Always pair the ADOS with a parent interview like the ADI-R before you share the diagnosis.

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Check which ADOS algorithm version your team scores with—switch to the 2007 revised or ADOS-2 rules if you haven’t yet.

02At a glance

Intervention
not applicable
Design
other
Sample size
223
Population
autism spectrum disorder, mixed clinical
Finding
not reported

03Original abstract

The Autism Diagnostic Observation Schedule-Generic (ADOS-G) is a semistructured, standardized assessment of social interaction, communication, play, and imaginative use of materials for individuals suspected of having autism spectrum disorders. The observational schedule consists of four 30-minute modules, each designed to be administered to different individuals according to their level of expressive language. Psychometric data are presented for 223 children and adults with Autistic Disorder (autism), Pervasive Developmental Disorder Not Otherwise Specified (PDDNOS) or nonspectrum diagnoses. Within each module, diagnostic groups were equivalent on expressive language level. Results indicate substantial interrater and test-retest reliability for individual items, excellent interrater reliability within domains and excellent internal consistency. Comparisons of means indicated consistent differentiation of autism and PDDNOS from nonspectrum individuals, with some, but less consistent, differentiation of autism from PDDNOS. A priori operationalization of DSM-IV/ICD-10 criteria, factor analyses, and ROC curves were used to generate diagnostic algorithms with thresholds set for autism and broader autism spectrum/PDD. Algorithm sensitivities and specificities for autism and PDDNOS relative to nonspectrum disorders were excellent, with moderate differentiation of autism from PDDNOS.

Journal of autism and developmental disorders, 2000 · doi:n/a