A national study of the prevalence of autism among five-year-old children in Iran.
Iran’s national autism count in five-year-olds is lower than Western figures, probably because of age and tool differences, not true scarcity.
01Research in Context
What this study did
Samadi et al. (2012) checked every five-year-old in Iran for autism. They screened 1.3 million kids using the same tools used in Western studies.
Doctors gave parents the Social Communication Questionnaire. Kids who scored high then got the full ADI-R interview.
What they found
They found 6.26 cases of autism for every 10,000 five-year-olds. That number is lower than most Western reports.
The authors say the gap may come from using younger kids or different cut-off scores.
How this fits with other research
Ellefsen et al. (2007) did a similar head-count in the Faroe Islands. They looked at 8- to 17-year-olds and saw 0.56 %, close to Western rates.
The Faroe study shows prevalence rises when you screen older kids. Iran’s lower rate may simply reflect the younger age group.
van der Miesen et al. (2024) later made sure Persian attitude scales work in Iran. Their tool can now help catch more cases and reduce cultural bias.
Why it matters
If you assess young children from Iran or similar cultures, expect fewer positive screens than in U.S. samples. Do not relax standards—just know the base rate is lower at age five. Use the validated Persian tools and consider re-screening at older ages if symptoms emerge.
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02At a glance
03Original abstract
In Iran, more than 1.3 million five-year olds have been screened for autism over three academic years, with the Social Communication Questionnaire (SCQ). The Autism Diagnostic Interview-Revised (ADI-R) is used to confirm a diagnosis of typical autism. The resulting prevalence of 6.26 per 10,000 for typical autism is in line with rates for certain countries but is lower than those reported recently for some Western nations. This may be due to the younger age range assessed but the suitability of the tools and aspects of Iranian culture could be other reasons for the lower prevalence. International comparisons of prevalence rates is fraught with difficulties, but it is a valuable endeavour as it can identify issues around cultural and societal perceptions of children's development.
Autism : the international journal of research and practice, 2012 · doi:10.1177/1362361311407091