Assessment & Research

Limited Effect of Masking During COVID-19 Pandemic on ADOS-2 Algorithm Scores in Toddlers With and Without Autism.

Angelina et al. (2025) · Autism research : official journal of the International Society for Autism Research 2025
★ The Verdict

ADOS-2 scores stay valid even when clinicians wear masks.

✓ Read this if BCBAs who give ADOS-2 in hospitals or clinics with mask rules.
✗ Skip if Teams still using only parent questionnaires like M-CHAT.

01Research in Context

01

What this study did

The team gave toddlers the ADOS-2 while the examiner wore a mask. They compared scores to the same kids tested earlier with no masks.

Toddlers had autism, other delays, or were neurotypical. The goal was to see if masks changed the final algorithm score.

02

What they found

Only 2 of 20 ADOS-2 items shifted at all. The total algorithm score stayed the same.

Masks did not change who met autism cut-offs.

03

How this fits with other research

Lancioni et al. (2006) showed the toddler ADOS already lines up well with expert judgment. Vernetti’s 2025 data add that masks do not break that agreement.

Mierau et al. (2026) found race made only tiny item-level ripples in preschool ADOS-2 scores. Vernetti saw the same pattern: masks tweak single items, not the final score.

Toh et al. (2018) warned that the M-CHAT misses many toddlers under 21 months. Together these papers tell us: use the right tool for the age, and small procedural changes like masking are not the weak link—picking the wrong screen is.

04

Why it matters

You can keep running ADOS-2 in clinics that require masks. The score you get is the score you would have got pre-COVID. Do not add extra visits just to see faces—save that time for treatment.

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Keep your masked ADOS-2 session—no score correction needed.

02At a glance

Intervention
not applicable
Design
quasi experimental
Sample size
348
Population
autism spectrum disorder, mixed clinical, neurotypical
Finding
null
Magnitude
negligible

03Original abstract

The Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) constitutes one of the most widely used diagnostic instruments for autism and involves a direct face-to-face interaction between clinician and child. During the COVID-19 pandemic, administration of the ADOS-2 continued in several countries, with the requirement of face mask protection. It has been hypothesized that mask wearing may have disrupted the dynamic of child-clinician interaction and differentially affected toddlers with autism. We compared ADOS-2 algorithm scores between cohorts of toddlers evaluated before (pre-COVID-19, n = 232) and during the pandemic (COVID-19, n = 116). The COVID-19 cohort included 41 toddlers with autism spectrum disorders (AUT, Mage = 25.4, SD = 3.8), 34 toddlers with other neurodevelopmental conditions (NDC, Mage = 22.3, SD = 5.0), and 41 typically developing toddlers (TD, Mage = 20.4, SD = 3.6) recruited between September 2020 and April 2023. The pre-COVID-19 cohort was selected from 409 assessments conducted from January 2013 to March 2020. Propensity matching was used to match the pre- and COVID-19 cohorts on sex, chronological age, and verbal and nonverbal developmental quotient (DQ) scores. Ordered logistic regression analyses were computed for social affect (SA) and restricted and repetitive behaviors (RRB) algorithm total and item scores, with cohort (pre-COVID-19/COVID-19) as a fixed factor for each diagnostic group. The analyses revealed a limited impact of cohort on the algorithm scores in all three diagnostic groups. Item-level analysis revealed a significant cohort effect only on two out of 20 items: shared enjoyment and joint attention, with higher (more atypical) scores found in the COVID-19 than in the pre-COVID-19 cohorts. The resiliency of the algorithm and item-level scores to the effect of masking speaks to the strength of the diagnostic tool and its ability to capture a range of social, communication, and repetitive behaviors under both standard and nonstandard conditions.

Autism research : official journal of the International Society for Autism Research, 2025 · doi:10.1002/aur.70050