Autism is an “epidemic,” if we accept the rhetoric of advocacy groups. But what is the real rate of autism? Is there an actual epidemic or are we more aware of autism and autistic traits that have existed for centuries? These are questions that can only be explored if we are able to establish a uniform methods for counting cases of autism.
Does autism affect 1 in 300 children? Or maybe it is 1 in 166? The most recent public service campaign by the Autism Society of America claims a rate of 1 in 150.
Today, the most widely accepted conservative estimates, which is to say, the lower estimates, are as follows: Autistic Disorder (13 / 10,000), PDD-NOS (21 / 10,000), Asperger’s Disorder (2.6 / 10,0000), which gives a combined rate of 36.6 / 10,000, or about 1 in 300.
... The less conservative and current best estimate for the whole range of autistic disorders, including cases of autism that may be diagnosed by clinicians and recorded in the IDEA child counts, but which may not meet DSM criteria, is about 60 in 10,000, or 1 in 166. In these less conservative estimates, Asperger cases account for between 14 and 19 percent of the total autism spectrum population. (Grinker, 2007, p. 163)
When we seek a precise rate of autism, we have to concern ourselves with the politics as much as the science. The diagnostic criteria used to identify autism need to be uniform, or the rates established are meaningless, scientifically. Yet the question of defining autism is incredibly political.
Higher rates of autism increase pressure on “science” and “government” to do something, anything, to deal with the perception of an epidemic.
Data collection can reveal patterns of diagnosis. Questions are then raised about concentrated reports of autism. Are there a geographical causal links or are regional diagnostic practices resulting in rate differences? Are the patterns ethnic? Economic?
Employing a uniform definition of autism becomes essential for both scientific data analysis and equitable distribution of public resources.
Autism Rates
Based on reports from the United States Dept. of Education, I have created several Autism rate tables for analysis.
There should be no doubt that the diagnosis of autism is increasing at an astonishing pace. Does this mean there are more cases or that we are better at detecting autism? Has awareness of autism increased the number of students screened for autism spectrum disorders?
It could be a mix of both higher actual rates and better diagnostic criteria. Unfortunately, only time can answer what is responsible for the rate increase. There is little doubt, however, that historical rates of autism are not accurate.
- Cultural biases against autism resulted in fewer reported cases in the past;
- Diagnostic criteria for autism disorders have improved substantially since 1994; and
- Public awareness of autism has increased a willingness to have children assessed by clinicians.
If criteria for the diagnosis change, or if we develop genetic screening for some forms of autism, rates from surveys we currently accept will be rendered meaningless.
The truth is that no one knows the exact rate of autism world-wide, in the United States, or even within a single state. The statistics we have are improving, but they will be revised for years to come.
Epidemic or Not?
The word “epidemic” is frequently misused in public debates. Using the term incorrectly is similar to declaring a “war” on every problem facing humanity: a war on poverty, war on crime, war on illiteracy, and so on. Maybe having a graduate degree in “rhetoric” makes me more sensitive to such manipulations of language, but I’d like to believe most people recognize the game being played.
Yes, mentioning the “autism epidemic” attracts media attention, but it there a real epidemic in scientific terms? Traditionally, an epidemic appeared suddenly, killed indiscriminately, and then vanished as suddenly as it arrived. Some medical historians and epidemiologists suggest an epidemic has to affect ten or even 20 percent of a population to earn the designation.
Oxford American Dictionary
epidemic (n) A disease that quickly and severely affects a large number of people and then subsides
Is there an autism epidemic? Scientifically, I lean towards no. But public policy and debates are not based on scientific accuracy. We should not have to resort to hyperbole to explain that autism is a serious problem.
The word “epidemic” is devolving and losing its essence thanks to politicians abusing it.
I wish to be very clear that I believe diagnosed cases of autism are increasing. I also believe we are likely to uncover a mix of genetic, contextual, and environmental factors behind the disorders we currently group together as autism spectrum disorders.
It is simply a hope that we can pursue research without encouraging parents to panic or politicians to spend recklessly.