Assessment & Research

Prevalence of Autism Spectrum Disorders in Guanajuato, Mexico: The Leon survey.

Fombonne et al. (2016) · Journal of autism and developmental disorders 2016
★ The Verdict

Autism prevalence in central Mexico is 0.87 %, matching today’s global 1 % benchmark.

✓ Read this if BCBAs building caseloads or training school teams in Mexico or Latin America.
✗ Skip if Clinicians only serving toddlers or adults.

01Research in Context

01

What this study did

Fombonne et al. (2016) counted how many 8-year-olds in León, Mexico have autism.

They checked school and health records. They used the same rules doctors use everywhere.

02

What they found

About 1 in every 115 children had autism. That is 0.87 %. The true number is likely between 0.62 % and 1.1 %.

03

How this fits with other research

Zeidan et al. (2022) put the Mexico number into a giant world map of 200 studies. The new map shows the global average is also 1 %. The Mexico finding sits right on that line.

Older papers saw much lower numbers. Fombonne (2003) found 0.3–0.6 %. Gaily et al. (1998) found only 0.04–0.05 %. The jump is not a real epidemic. Doctors now count milder cases and use wider labels.

Similar city studies match León. Mansell et al. (2002) in the UK saw 0.6 %. Wong et al. (2025) in Hong Kong saw 2.6 %. Different places, similar 1 % neighborhood.

04

Why it matters

You can tell parents and teachers that 1 % is the best working number for Mexico and most countries. When you screen, expect about one child with autism in every 100 eight-year-olds. Use this fact to plan classes, train staff, and fight stigma. The number is not exploding; awareness is just catching up.

Free CEUs

Want CEUs on This Topic?

The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.

Join Free →
→ Action — try this Monday

Use 1 % when you explain to teachers how many kids with autism to expect in third grade.

02At a glance

Intervention
not applicable
Design
survey
Sample size
12116
Population
autism spectrum disorder
Finding
not reported

03Original abstract

There are no epidemiological data on autism for Mexico. This study was conducted to generate a first estimate of ASD prevalence in Mexico. We surveyed children age eight in Leon (Guanajuato). The sample was stratified in two strata: (1) children having special education and medical records (SEMR; N = 432) and (2) children attending regular schools (GSS; N = 11,684). GSS children were screened with the SRS and those with the highest scores were invited to a diagnostic evaluation. The final sample comprised 36 children (80.6 % male) who had confirmed ASD. A third had intellectual disability, 25 % were non-verbal, 69 % had co-occurring behavioral problems. The prevalence overall was 0.87 % (95 % CI 0.62, 1.1 %). This survey provides an estimate for ASD prevalence in Mexico that is consistent with recent studies.

Journal of autism and developmental disorders, 2016 · doi:10.1007/s10803-016-2696-6