There has been so much written recently about the world-wide increase in the number of children with autism that this issue demands a bit of investigation. We will begin by looking at some of the publicity about the rising cases of autism"

1. Issues About Incidence And Prevalence Of Autism
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Biography of David J. Carey:
David was employed for many years as the Coordinator of Special Education and
Programme Development at the Froebel College of Education, one of Ireland’s five
primary teacher-training colleges. He has recently decided to pursue his primary
interests, the private practice of psychology and writing books. He is a psychologist
with 25 years experience in both clinical and educational settings. He has worked
with children, adolescents and adults having a variety of emotional and behavioural
difficulties including Oppositional Defiant Disorder, ADHD, Conduct Disorder as well
as serious mental health problems such as bi-polar disorder and schizophrenia. At
Froebel he has lectured in special education and coordinated several post-graduate
programmes including a Master’s degree in special education. He is a part-time
lecturer on the Master’s in educational psychology and special education at University
College Dublin, an occasional lecturer at Roehampton University, London and at
Trinity College Dublin.
David is the author of The Essential Guide to Special Education in Ireland
and is on the editorial board of REACH, the journal of the Irish Association of Special
Education Teachers. He is currently completing a guide to the education of children
with autistic spectrum disorders in mainstream schools. He has published extensively
in Ireland and in the US on various mental health topics and special education issues.
He has lectured internationally and currently is the director of an educational
development programme in Nairobi Kenya, working with Kindergarten teachers and
providing volunteer teachers in the slum schools of Kabira, Africa’s largest slum.
Private Practice:
David includes the following specialities in his private practice:
1.) Hypnosis for self-esteem, self-confidence and habit control
2.) Individual therapy of adolescents and adults
3.) Assessment of children, adolescents and adults
4.) Assessment of child-custody issues
5.) Assessment of ADHD in children, adolescents and adults
6.) Individual cognitive-behaviour therapy for ADHD in adolescents and adults
7.) Group therapy for adults
For an appointment or additional information please call: +353 (0)86 8115764
Email Me: info@davidjcarey.com
_____________________________________________________________________________________
www.davidjcarey.com

2. Issues About Incidence And Prevalence Of Autism
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ISSUES ABOUT INCIDENCE AND
PREVALENCE OF AUTISM
quot;There has been so much written recently about the world-wide increase in the number
of children with autism that this issue demands a bit of investigation. We will begin by
looking at some of the publicity about the rising cases of autismquot;
In the 5/09/07 issue of The Californian found on the Internet the following statistics are
quoted about enrolment of children with autism in elementary (primary) schools:
“In the Temecula and Lake Elsinore school districts, their
populations have jumped by about 300 percent. In the Murrieta
school district, the autistic enrolment has grown by 650 percent,
an increase of about 100 students.”
In 2001 an article appeared on the Internet titled “The Geek Syndrome”. It looked at
the incredible rise in cases of autism in silicon valley, a part of California known for its
high achieve and high absorbed software developers. In the article the following is
stated:
In the past decade, there has been a significant surge in the number of kids diagnosed
with autism throughout California.
In August 1993, there were 4,911 cases of so-called level-one autism logged in the state's
Department of Developmental Services client-management system. This figure doesn't
include kids with Asperger's syndrome, like Nick, but only those who have received a
diagnosis of classic autism. In the mid-'90s, this caseload started spiralling up. In 1999,
the number of clients was more than double what it had been six years earlier. Then
the curve started spiking.
quot;By July 2001, there were 15,441 clients in the DDS database. Now
there are more than seven new cases of level-one autism - 85
percent of them children - entering the system every day.”
Figures release by the US Dept. of Education in noting the numbers of cases of autism
diagnosed between 1992 and 2000 revealed the following statistics (IDEA is the federal
law protecting children with disabilities to a free and appropriate education.
From the Department of Education annual reports to the US Congress
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3. Issues About Incidence And Prevalence Of Autism
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(Children with a diagnosis of autism aged 6-21] served by IDEA
(Individuals With Disabilities Education Act)
(Source: US Individuals With Disabilities Education Act data:
http://www.IDEAdata.org/tables/ar_aa2.htm )
“In round terms, for every two children registered through IDEA with autism in 1992-93,
there were almost eleven by 1999-2000.”
On Tuesday, 27/02/01 the BBC News issued a report that stated the cases of autism
in the UK had increased ten-fold over the past decade.
What sense can we make of these statistics? Before attempting to look at the possible
factors involved in this incredible rise in cases it is important to unpack some
vocabulary. The terms “incidence” and “prevalence” connote the same concepts to the
lay reader, yet they are not the same thing at all.
Incidence vs. Prevalence
Prevalence is a frequently used measure of how commonly a disease or conditions
occurs in a given population. It measures just how much of the condition is present
in a population at any given point in time. It is sometimes called “point prevalence”.
Prevalence is calculated by dividing the number or persons with the condition at a
particular point in time by the number of persons examined for the condition.
Prevalence can be expressed as either a percentage or, if the number is low, as the
number of cases per a given number of population (e.g. 10 in 10,000).
Incidence measures the number of new cases of a condition. Incidence is usually
calculated by the number of new cases of a condition (or disease) in a specified
time period (usually one year) divided by the size of the population being studied
who are initially free of the condition (or disease).
Any intelligent interpretation of the rise in autism must take into account the
definition of incidence and prevalence outlined above.
What Accounts for the Rise in Autism?
Does the measles-mumps-rubella vaccine cause autism? Probably no question is more
vexing to so many parents than this one. Fortunately, around the world there have
been numerous studies looking for the answer. At present the weight of scientific
evidence does not support the theory that the MMR vaccine causes autism. There is
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4. Issues About Incidence And Prevalence Of Autism
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enough continued interest in the theory however to result in the Center for Disease
Control in Atlanta, Georgia to continue to investigate.
What is the basis of this theory?
It was Wakefield, writing in the UK who first introduced statistics that linked the MMR
vaccine to autism. Writing in the UK medical journal The Lancet, senior author Andrew
Wakefield wrote a five-page “early report” suggesting that the MMR vaccine was
associated with inflammatory bowled disease and regressive autism. (Regressive
autism is a term for the type of autism associated with early normal development
followed by the onset of autistic symptoms.) The number of children studied by
Wakefield and his associates was 12. Media attention was swift and world-wide.
Headlines associated the vaccine with autism.
Since 16 July, 2007 Wakefield and his colleagues are facing charges of serious
professional misconduct in relation to this study. For an interesting, in-depth read on
this topic please see the following web page:
http://briandeer.com/mmr/lancet-summary.htm
Because the publicity surrounding Wakefield’s study was so massive (and a lot of it the
direct result of the efforts of the hospital in which it was undertaken) parents world-side
have been traumatised by wondering if they did not inadvertently cause their child’s
autism. Also associated with the publicity surrounding the study was a marked
decrease in the number of children being vaccinated. Vaccination rates in Britain are
now running at about 80%. For “herd-immunity” to be present the vaccination rate
needs to be about 92%.
Let’s look at the Facts
A study of 30,000 children in Yokohama, Japan in provides an interesting insight into
the issue of MMR and autism. Prior to this study no investigation of the connection had
ever been completed on a population who had no access to the vaccine. In Japan in
the vaccine was removed in April 1993 because there was a fear it might be associated
with meningitis (related solely to the anti-mumps component of the vaccine). This study
looked at 31,426 children born in one district of Yokohama between the years 1988 and
1996. Only children diagnosed with autism by the age of 7 were included in the
study. It was found that cases of autism continued to multiply after the vaccine
withdrawal. Before the vaccine was withdrawn the number of cases was 48 to 86 per
10,000 children. After the vaccine was withdrawn the number of cases rose to 97 to 161
per 10,000! Interestingly, the same pattern was found for a group of children with a
particular form of autism (normal development and then loss of function) that had been
described by Wakefield in his original UK study. The study cannot rule-out the
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5. Issues About Incidence And Prevalence Of Autism
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possibility that the vaccine causes autism in a small number of children but clearly
indicates there is no large-scale cause and effect, at least in Yokohama, Japan.
In his book “Unstrange Minds: Remapping the World of Autism”, author Roy
Richard Grinker undertook a world-wide investigating to explore the issue of rising
cases of autism. His conclusion: there is no rise! The identification of autism depends
on culture as much as on science (this is a position I myself have taken in earlier parts
of this book.) He also reasons that more effective diagnosis, more attention to the
condition in the media and better educational structures all account for the rise in
autism cases worldwide.
Why do people continue to believe the autism-MMR link?
Autism can be accurately diagnosed by the age of three (some speculate that it can be
diagnosed at age 1). This is about the same age as vaccinations are given to children.
AS a result there will always be an apparent association between the vaccine and
autism. The can easily be the result of chance alone. There is also considerable
mistrust in the scientific community amongst lay people. These two factors combine
with heart-wrenching personal testimonials from some parents along the lines of “Why
won’t someone stop this madness?” that continue to decry the use of the MMR vaccine.
It is only natural for people to search for answer but the apparent link between autism
and the vaccine just has not born out under the weight of considerable scientific
scrutiny.
What can we conclude?
Maybe it’s a bit early to come to any conclusion but some things are evident.
Statistics can be misleading. Charts that purport to show a rise in autism must take
into account some important factors: rise in population in the place being studied,
change of diagnostic criteria over the last 15 years and the earlier age of diagnosis
now commonly achieved.
Also the meaning of “incidence” and “prevalence” must be accounted. Certainly the
incidence of autism is on the increase but that does not mean the prevalence is
increasing. If you remain confused please re-read the section that defines the terms at
the beginning of this chapter.
http://www.nctimes.com/articles/2007/03/11/news/californian/21_36_103_10_07.txt
http://www.wired.com/wired/archive/9.12/aspergers_pr.html
BBC News, 27 February 2001
The Lancet, volume 351, Number 9103, 28 February 1998
New Scientist, 17 February 2001
Grinker, R. R. (2007). Unstrange Minds: Remapping the World of Autism. New York: Basic Books
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www.davidjcarey.com

6. Issues About Incidence And Prevalence Of Autism
_____________________________________________________________________________________
Biography of David J. Carey:
David was employed for many years as the Coordinator of Special Education and
Programme Development at the Froebel College of Education, one of Ireland’s five
primary teacher-training colleges. He has recently decided to pursue his primary
interests, the private practice of psychology and writing books. He is a psychologist
with 25 years experience in both clinical and educational settings. He has worked
with children, adolescents and adults having a variety of emotional and behavioural
difficulties including Oppositional Defiant Disorder, ADHD, Conduct Disorder as well
as serious mental health problems such as bi-polar disorder and schizophrenia. At
Froebel he has lectured in special education and coordinated several post-graduate
programmes including a Master’s degree in special education. He is a part-time
lecturer on the Master’s in educational psychology and special education at University
College Dublin, an occasional lecturer at Roehampton University, London and at
Trinity College Dublin.
David is the author of The Essential Guide to Special Education in Ireland
and is on the editorial board of REACH, the journal of the Irish Association of Special
Education Teachers. He is currently completing a guide to the education of children
with autistic spectrum disorders in mainstream schools. He has published extensively
in Ireland and in the US on various mental health topics and special education issues.
He has lectured internationally and currently is the director of an educational
development programme in Nairobi Kenya, working with Kindergarten teachers and
providing volunteer teachers in the slum schools of Kabira, Africa’s largest slum.
Private Practice:
David includes the following specialities in his private practice:
1.) Hypnosis for self-esteem, self-confidence and habit control
2.) Individual therapy of adolescents and adults
3.) Assessment of children, adolescents and adults
4.) Assessment of child-custody issues
5.) Assessment of ADHD in children, adolescents and adults
6.) Individual cognitive-behaviour therapy for ADHD in adolescents and adults
7.) Group therapy for adults
For an appointment or additional information please call: +353 (0)86 8115764
Email Me: info@davidjcarey.com
_____________________________________________________________________________________
www.davidjcarey.com