Prevalence of Autism

Over the past 40 years, there appears to have been a steady increase in the number of children/young people diagnosed with autism (Baird et al, 2006; Baron-Cohen et al, 2009; Filipek et al, 1999; Fombonne, 2003; National Audit Office, 2009). This may be due to improved diagnostic tests, widening of the diagnostic criteria, less stigmatisation of the condition and an increased awareness from health professionals and families alike (Baron-Cohen et al, 2009).

Globally, it is estimated that between 1.13% and 2.64% (Baio, 2012; Kim et al., 2011) of children will be diagnosed with autism.

The National Council for Special Education (NCSE) found that one in every 65 students or 1.5% of the school population in Ireland had a diagnosis of autism:

The Department of Education and Skills (Republic Of Ireland) has reported that ‘autism is no longer thought of as a rare disorder’ (DfES, 2006 [Wilkinson & Twist]). Similarly, in a UK wide survey of 373 teachers, 67% reported that they felt there were more children with autism now than five years ago in both special and mainstream education (Barnard et al., 2002).

The Information Analysis Directorate (part of DHSSPSNI) produced a report on the prevalence of autism (including Asperger syndrome) in school aged children in Northern Ireland which was published in May 2019. This report is based on the prevalence rates of ASD amongst compulsory school age children (attending grant-aided schools) (4-15 years old at the start of the school year). The prevalence rate was calculated at 3.3%.

To read this report in full, click here.

It is estimated that that there are over half a million people in the United Kingdom with ASD. This is approximately 1% of the population and if families are included, it is estimated that autism affects the lives of over two million people (

Autism is more prevalent in males than in females, research indicates that girls with autism are often detected and diagnosed later than their male peers.

For additional information on autism and girls please click here for Middletown Centre for autism Research Bulletin