Age at autism spectrum disorder diagnosis: A systematic review and meta-analysis from 2012 to 2019.
Autism is still spotted around age five worldwide, so screen early and act fast.
01Research in Context
What this study did
The team pooled 2012-2019 data from 40 countries. They asked one simple question: how old are children when they first get an autism diagnosis?
No new tests were run. They combined published studies to find the global average age.
What they found
The average age of diagnosis is still about five years old. That number has barely moved in decades.
Kids wait roughly 60 months even though warning signs show up much earlier.
How this fits with other research
Rattaz et al. (2022) looked only at France and found the same five-year mark. Their work shows kids with intellectual disability or severe symptoms get spotted closer to age three, while milder cases slip past five.
Davidovitch et al. (2023) studied 258 children diagnosed after age six. Many had earlier labels like “language delay” or “ADHD” and were already on meds. Together these papers paint a clear picture: early signs are missed and children linger in diagnostic limbo.
Tan et al. (2021) ran a sister meta-analysis the same year. They tracked when children lose skills, not when they get diagnosed. About one in three kids regress around 19 months, yet the average diagnosis still lands at five years—showing a three-year gap between first red flags and formal identification.
Why it matters
You can’t treat what you don’t see. Every extra year of delay steals intervention time. Use routine screening at 18 and 24 months, and re-check any school-age child with peer problems or prior language-delay labels. Push for expedited evaluation; families are counting on you to shorten the wait.
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02At a glance
03Original abstract
We currently assume that the global mean age at diagnosis of autism spectrum disorder ranges from 38 to 120 months. However, this range is based on studies from 1991 to 2012 and measures have since been introduced to reduce the age at autism spectrum disorder diagnosis. We performed a systematic review and meta-analysis (statistical analysis that combines the results of multiple scientific studies) for studies published between 2012 and 2019 to evaluate the current age at autism spectrum disorder diagnosis. We included 56 studies that reported the age at diagnosis for 40 countries (containing 120,540 individuals with autism spectrum disorder). Results showed the current mean age at diagnosis to be 60.48 months (range: 30.90-234.57 months) and 43.18 months (range: 30.90-74.70 months) for studies that only included children aged ⩽10 years. Numerous factors that may influence age at diagnosis (e.g. type of autism spectrum disorder diagnosis, additional diagnoses and gender) were reported by 46 studies, often with conflicting or inconclusive results. Our study is the first to determine the global average age at autism spectrum disorder diagnosis from a meta-analysis. Although progress is being made in the earlier detection of autism spectrum disorder, it requires our constant attention.
Autism : the international journal of research and practice, 2021 · doi:10.1177/1362361320971107