Prevalence Estimates Around the World
A recent systematic review from Autism Research looked at the data from 71 studies on autism prevalence worldwide from 2012 to 2021. Prevalence refers to the number of people in a specific population that have a condition. Prevalence is commonly shown as a proportion.
This study found that about one in 100 children around the world is diagnosed with autism. This means that for every 100 children around the world, one child will be diagnosed with autism.
The study also measured the number of males versus females that are diagnosed with autism using a gender ratio. A gender ratio compares the number of males to females diagnosed with autism by dividing the number of males with autism by the number of females with autism. A number over 1 means that there are more males with autism, and a number less than 1 means there are more females with autism.
This study found that the gender ratio worldwide was 4.2. This means that males are a little more than 4 times as likely to be diagnosed with autism than females.
There are differences in the prevalence and gender ratio of autism in different regions of the world. The following table shows the median (middle of the data set) for the prevalence and gender ratio in different regions of the world.
Trends in Autism Around the World
By studying many different groups of people with autism all around the world, researchers can begin to see if trends seen in one location apply to others. In this study, scientists looked at a few key areas to gain a better understanding of how autism affects different groups—gender, sociodemographic status, race and ethnicity, and how the diagnosis of autism has changed over time.
The ratio of males and females with autism worldwide is the same as the ratio measured by the CDC in the US, which is 4.2. Autism is not as common in girls around the world. However, when girls are diagnosed with autism, it is more likely to occur along with intellectual disability.
Most of the studies examining sociodemographic status come from the US. The factors that make up sociodemographic status include geographic location and economic factors.
In the US, Missouri has the lowest rate of autism (96 per 10,000 in 2014) and New Jersey has the highest rate of autism (284 per 10,000 in 2014).
Some studies in India found higher rates of autism in rural areas when compared to urban areas. The opposite was found in Taiwan, where autism was more common in urban areas compared to rural areas. A study in Greece did not find any difference in the prevalence of autism between urban and rural areas.
Race and Ethnicity
The US consistently monitors racial disparities in the diagnosis of autism. In the past, racial minorities have been underdiagnosed. However, data from 2016 shows nearly identical prevalence rates for white, non-Hispanic, black, and Asian/Pacific Islander children. This is a significant change from a 2010 study that found that non-Hispanic white children were about 2.5 times more likely to be diagnosed with autism.
Trends Over Time
Since the last report on the global prevalence of autism in 2012, there has been an increase in prevalence worldwide. In 2012, the prevalence of autism was 62 in 10,000. In 2022, the prevalence is 100 in 10,000 children, which is the same as one in 100 children.
Monitoring the number of people diagnosed with autism around the world is an important part of increasing autism awareness. Although prevalence studies do not answer the question of what causes autism, they do give important insights into risk factors. These studies also highlight where more services may be needed.
Songbird Therapy is a technology-enabled provider setting a higher standard for children’s autism care. With a deeply passionate team and innovative technology, we’re building a world where every child can access world-class care at home, uniquely tailored to them.