Assessment & Research

Diagnosis of autism in adulthood: A scoping review.

Huang et al. (2020) · Autism : the international journal of research and practice 2020
★ The Verdict

Adult autism diagnosis is a maze with no map and no exit support.

✓ Read this if BCBAs who see adults questioning autism or needing post-diagnosis care.
✗ Skip if Clinicians who only work with children under 18.

01Research in Context

01

What this study did

The authors searched every paper on adult autism diagnosis from 2000 to 2020.

They looked at 78 studies from 17 countries.

They wanted to see how adults get tested and what happens after.

02

What they found

No two places use the same steps to test adults.

Most adults feel relief, shock, or grief after hearing the news.

Few get any follow-up help.

03

How this fits with other research

Jackson et al. (2025) shows one way to fix the gap. They tested a strengths-based feedback session that adults loved.

Lineberry et al. (2023) proves the need is huge. Only 4 in 10 UK adults get support within a year of diagnosis.

Billstedt et al. (2005) warns us why this matters. Most adults diagnosed as kids still struggle to live on their own decades later.

04

Why it matters

You may meet adults who wonder if they are autistic. This paper tells you they will likely leave testing with big feelings and no plan. You can step in by offering a short feedback session that names strengths, lists next steps, and books a follow-up visit.

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02At a glance

Intervention
not applicable
Design
scoping review
Population
autism spectrum disorder
Finding
not reported

03Original abstract

More adults are getting assessed for possible autism. Here, we give an overview on what is already known about autism diagnosis in adulthood and find areas that need more research. We divided results from the studies we found into six topics of (1) rates of autism in different groups; (2) the process of getting an autism diagnosis in adulthood; (3) gender; (4) personality traits, abilities and behaviours of diagnosed adults; (5) mental and physical health conditions that occur together with autism; and (6) how adults think and feel about being assessed and diagnosed. We found that adults often have strong emotions after being diagnosed, the process of getting a diagnosis can be unclear and different for everyone, and not many support services are available for adults. More research on diagnosing adults with intellectual disability, differences between early and late-diagnosed adults, and support after diagnosis would be useful.

Autism : the international journal of research and practice, 2020 · doi:10.1177/1362361320903128