Research
Understanding what "1 in 100" means for Autistic Disorder
10/11/09 15:38
There have been a number of items in the news over the past couple of weeks regarding changes in our understanding about the prevalence of autism (I was even briefly in a television interview on the subject), and these items, when taken together, begin to shape up in an interesting fashion.
Probably the most heralded item was The Center's for Disease Control (CDC) October 5, 2009 press release announcing recent research supporting a prevalence rate for Autism of 1 in 100 people, or about 1% of the general population. This rate is higher than the previously reported 1 in 150 people, of course, and at first blush continues to support the concept that autism is on the rise. However, close attention to the other information that has come out is vital when looking at the overall picture.
The study referred to by the CDC was published in the journal Pediatrics (a PDF of the article is available here - I find the Pediatrics website difficult to navigate quickly). The study used a very large sample (over 78000 participants) of children from 3 to 17 years of age. It was conducted by randomly dialing U.S. telephone numbers and conducting interviews with the parents who answered the phone. Parents were asked "if they had ever been told by a doctor or other health care provider that their child had 'autism, Asperger disorder, pervasive developmental disorder, or other autism spectrum disorder'. Parents who indicated that they had been given such a diagnosis for their child were then asked if the child currently had autism. When the parent answered "yes" to both questions the child was included in the overall total". The results from this process was that reported 110 in 10,000 respondents indicated "yes" to both questions, resulting in an extrapolated prevelance rate of right around 1 in 100, or 1% of the general population.
When we begin to look at results like this it becomes clear how important the choice of language can be to understanding these types of results. In some cases this is referred to as an "increase in the prevalence" of autism - a phrase which implies that the disorder is increasing in frequency among our population. In scientific writing, however, we are taught to be very careful with our phrasing to prevent such implications, and this is a case in point. The results of this clearly well-done and important study would be more accurately described as providing a change in our understanding about the prevalence of autism.
A study released at nearly the same time as the article in Pediatrics demonstrates this point extremely well. A study completed by the National Health Service in Great Britain looked at rates of autistic disorder among adults in that nation. That study found a prevalence rate of 1 in 100 or 1% - essentially identical to the CDC's findings for children.
The study's design is quite similar to that of the study completed by the CDC, though it uses a much smaller sample (but still over 7,000 respondents) for it's phone survey. However, in the NHS study the researchers also completed the Autism Diagnostic Observation Schedule (ADOS) - the current gold standard for autism assessment - on a subset of the respondents to further evaluate their findings. Even with evaluation using the ADOS the 1% prevalence rate held.
To my knowledge, the NHS study is the first of it's kind to investigate the prevalence of autism among adults - something we certainly must understand before we assume that the actual prevalence is rising. The results of the NHS study strongly support the idea that there are, in fact, a large number of adults in the general population with disorders in the autism spectrum. Further, those numbers are nearly identical to the numbers we are detecting in children today.
That we have not previously looked at prevalence rates among adults points to an area of concern that has been noted among professionals who work with both children and adults with developmental disabilities: Virtually all of the research in autism has been focused upon children. This is certainly understandable, as it's in childhood when we can most help.
Still, those of us who travel in both circles (child and adult treatment) have suspected for some time that there are a large number of undiagnosed adults on the spectrum in a variety of settings. I, along with several other members of the Forest City Team, have had the opportunity to work with adults in both community and institutional residential settings who clearly met the diagnostic criteria for disorders on the spectrum, but who had never been diagnosed (and in many of the cases the symptom presentation was not subtle). This is becoming thankfully less common as understanding of Autism Spectrum Disorder increases among professionals.
These studies add immensely to our understanding of what autism looks like in the general population, and, taken together, will hopefully help us understand where to most effectively focus our efforts to best assist others.
Probably the most heralded item was The Center's for Disease Control (CDC) October 5, 2009 press release announcing recent research supporting a prevalence rate for Autism of 1 in 100 people, or about 1% of the general population. This rate is higher than the previously reported 1 in 150 people, of course, and at first blush continues to support the concept that autism is on the rise. However, close attention to the other information that has come out is vital when looking at the overall picture.
The study referred to by the CDC was published in the journal Pediatrics (a PDF of the article is available here - I find the Pediatrics website difficult to navigate quickly). The study used a very large sample (over 78000 participants) of children from 3 to 17 years of age. It was conducted by randomly dialing U.S. telephone numbers and conducting interviews with the parents who answered the phone. Parents were asked "if they had ever been told by a doctor or other health care provider that their child had 'autism, Asperger disorder, pervasive developmental disorder, or other autism spectrum disorder'. Parents who indicated that they had been given such a diagnosis for their child were then asked if the child currently had autism. When the parent answered "yes" to both questions the child was included in the overall total". The results from this process was that reported 110 in 10,000 respondents indicated "yes" to both questions, resulting in an extrapolated prevelance rate of right around 1 in 100, or 1% of the general population.
When we begin to look at results like this it becomes clear how important the choice of language can be to understanding these types of results. In some cases this is referred to as an "increase in the prevalence" of autism - a phrase which implies that the disorder is increasing in frequency among our population. In scientific writing, however, we are taught to be very careful with our phrasing to prevent such implications, and this is a case in point. The results of this clearly well-done and important study would be more accurately described as providing a change in our understanding about the prevalence of autism.
A study released at nearly the same time as the article in Pediatrics demonstrates this point extremely well. A study completed by the National Health Service in Great Britain looked at rates of autistic disorder among adults in that nation. That study found a prevalence rate of 1 in 100 or 1% - essentially identical to the CDC's findings for children.
The study's design is quite similar to that of the study completed by the CDC, though it uses a much smaller sample (but still over 7,000 respondents) for it's phone survey. However, in the NHS study the researchers also completed the Autism Diagnostic Observation Schedule (ADOS) - the current gold standard for autism assessment - on a subset of the respondents to further evaluate their findings. Even with evaluation using the ADOS the 1% prevalence rate held.
To my knowledge, the NHS study is the first of it's kind to investigate the prevalence of autism among adults - something we certainly must understand before we assume that the actual prevalence is rising. The results of the NHS study strongly support the idea that there are, in fact, a large number of adults in the general population with disorders in the autism spectrum. Further, those numbers are nearly identical to the numbers we are detecting in children today.
That we have not previously looked at prevalence rates among adults points to an area of concern that has been noted among professionals who work with both children and adults with developmental disabilities: Virtually all of the research in autism has been focused upon children. This is certainly understandable, as it's in childhood when we can most help.
Still, those of us who travel in both circles (child and adult treatment) have suspected for some time that there are a large number of undiagnosed adults on the spectrum in a variety of settings. I, along with several other members of the Forest City Team, have had the opportunity to work with adults in both community and institutional residential settings who clearly met the diagnostic criteria for disorders on the spectrum, but who had never been diagnosed (and in many of the cases the symptom presentation was not subtle). This is becoming thankfully less common as understanding of Autism Spectrum Disorder increases among professionals.
These studies add immensely to our understanding of what autism looks like in the general population, and, taken together, will hopefully help us understand where to most effectively focus our efforts to best assist others.
Autism and Lupron
05/21/09 05:49
The Chicago Tribune has an excellent and disturbing article in today's paper about a small group of practitioners who are prescribing Lupron, a drug that shuts down the production of testosterone in males, for treatment of autism.
The author, Trine Tsourderos, does an excellent job of investigating many of the key points that we often discuss here in terms of investigating and critically analyzing claims. Among other key points, according to the article, it notes that the practitioners developing this "treatment" have no specialty or background in either autism, or the types of medicine subspecialties that would provide training and background either in the treatment of autism or in endocrinology, the type of specialty that would typically oversee treatment with Lupron.
But perhaps most telling is the fact that the developer himself is directly quoted as claiming that "Lupron is the miracle drug". As Carl Sagan once said "extraordinary claims require extraordinary evidence." Any time someone - anyone - is claiming miraculous results it should be a red flag.
It is a sad but completely unsurprising fact that despite the completely unproven - and frankly uninvestigated - nature of this treatment, the practitioners have been opening clinics in a sort of franchise model across the country. This begins to make fairly clear the motivation behind their approach...
The author, Trine Tsourderos, does an excellent job of investigating many of the key points that we often discuss here in terms of investigating and critically analyzing claims. Among other key points, according to the article, it notes that the practitioners developing this "treatment" have no specialty or background in either autism, or the types of medicine subspecialties that would provide training and background either in the treatment of autism or in endocrinology, the type of specialty that would typically oversee treatment with Lupron.
But perhaps most telling is the fact that the developer himself is directly quoted as claiming that "Lupron is the miracle drug". As Carl Sagan once said "extraordinary claims require extraordinary evidence." Any time someone - anyone - is claiming miraculous results it should be a red flag.
It is a sad but completely unsurprising fact that despite the completely unproven - and frankly uninvestigated - nature of this treatment, the practitioners have been opening clinics in a sort of franchise model across the country. This begins to make fairly clear the motivation behind their approach...
Genetic Links in Autism
04/29/09 05:30
The Chicago Tribune is reporting, in an article dated for today, on a pair of studies reported in the Journal Nature that relate to advances in research on genetic variations in autistic disorder. The entire text of the study article is available at Nature's website for those with advanced training in genetics and/or molecular biology (a group I am most certainly not among).
Information about study size, and design however, which are important components in determining the relative quality of research, are more universal research components. It is notable that this was a fairly good sized study, involving over 5,000 participants with autism spectrum disorders, and a very large control group. Autism diagnoses were made using the ADOS and/or the ADI-R, which would suggest good reliability and consistency in diagnosing autism amongst the participants. Read More...
Information about study size, and design however, which are important components in determining the relative quality of research, are more universal research components. It is notable that this was a fairly good sized study, involving over 5,000 participants with autism spectrum disorders, and a very large control group. Autism diagnoses were made using the ADOS and/or the ADI-R, which would suggest good reliability and consistency in diagnosing autism amongst the participants. Read More...
Always Look Beyond the Claims
04/21/09 14:28
Recently I had a consultation in Sandwich, Illinois, which meant that I had the opportunity to drive through the countryside on what must certainly have qualified as the loveliest day so far this spring. This type of opportunity is one of the more pleasant side effects of serving a largely rural area.
As I was driving down Route 30 - once referred to by Car and Driver as the Heartland Highway (I swear it was, though I cannot find a valid reference at this point) - I encountered a sign that says “NO WIND FARMS” with a web address at the bottom of it. I was curious enough to stop by the roadside and take a picture of it, and to check out the web address when I got back to the office.
Up front I should note that I have a considerable amount of personal interest and curiosity in alternative energy choices and sources. What I expected to find at the website, frankly, was a bit of propaganda about why having wind farms would be a bad thing - ruins the view, lowers property values, etc.
However, what struck me most - and disheartened me a bit - was a reference to a study, completed by a medical doctor - one Michael A. Nissenbaum - that suggests that people living within a few thousand feet of the turbines are experiencing health effects - headaches, difficulty sleeping, increased need for prescription medications, etc.
Any consumer of scientific information should be aware that the claims made by researchers and others are only as good as their research techniques and level of objectivity. This is extremely important in our field, as parents and professionals supporting and working with people who have developmental disabilities are routinely bombarded with various and sundry claims surrounding treatment for one thing or another, often with little to no good research to support it. I found with a bit of looking about online that this situation - like our review of the 2006 study of the relationship between television viewing and autism (which I will re-post soon to make available for reference) - presented a nice opportunity for evaluation of scientific claims. Read More...
As I was driving down Route 30 - once referred to by Car and Driver as the Heartland Highway (I swear it was, though I cannot find a valid reference at this point) - I encountered a sign that says “NO WIND FARMS” with a web address at the bottom of it. I was curious enough to stop by the roadside and take a picture of it, and to check out the web address when I got back to the office.
Up front I should note that I have a considerable amount of personal interest and curiosity in alternative energy choices and sources. What I expected to find at the website, frankly, was a bit of propaganda about why having wind farms would be a bad thing - ruins the view, lowers property values, etc.
However, what struck me most - and disheartened me a bit - was a reference to a study, completed by a medical doctor - one Michael A. Nissenbaum - that suggests that people living within a few thousand feet of the turbines are experiencing health effects - headaches, difficulty sleeping, increased need for prescription medications, etc.
Any consumer of scientific information should be aware that the claims made by researchers and others are only as good as their research techniques and level of objectivity. This is extremely important in our field, as parents and professionals supporting and working with people who have developmental disabilities are routinely bombarded with various and sundry claims surrounding treatment for one thing or another, often with little to no good research to support it. I found with a bit of looking about online that this situation - like our review of the 2006 study of the relationship between television viewing and autism (which I will re-post soon to make available for reference) - presented a nice opportunity for evaluation of scientific claims. Read More...
TV Does Not Cause Autism
10/17/06 14:25
Note - This is a re-publication of an article from 2006 (there has not a three year-gap in postings). When we re-designed the site recently we did not re-post all of the previous entries, though we will be adding in those which seem especially relevant. This article is the first archived entry to be added, as it is referenced in a current posting - EJW
This morning (10/17/06) an article appeared on Slashdot referring to a study that ostensibly claimed that television watching causes autism.
As has become very common in our media-driven society, the concepts and information in the study were significantly simplified for the article, and conclusions were drawn that the study, nor its authors, could possibly support. Unfortunately, when it comes to our children, and particularly disorders as puzzling as autism, everyone dealing with it – parents, professionals, administrators – is desperately hungry for any advance in understanding. This being the case, information presented in this shorthand way quickly becomes accepted fact, despite it’s not being an accurate representation of the available information. Given this, I am very concerned that we will very soon be hearing it stated, as if it were established fact, that television causes autism.
In light of this, let me say up front that this entry probably should be more accurately titled “this article does not show that TV watching causes autism”. Read More...
This morning (10/17/06) an article appeared on Slashdot referring to a study that ostensibly claimed that television watching causes autism.
As has become very common in our media-driven society, the concepts and information in the study were significantly simplified for the article, and conclusions were drawn that the study, nor its authors, could possibly support. Unfortunately, when it comes to our children, and particularly disorders as puzzling as autism, everyone dealing with it – parents, professionals, administrators – is desperately hungry for any advance in understanding. This being the case, information presented in this shorthand way quickly becomes accepted fact, despite it’s not being an accurate representation of the available information. Given this, I am very concerned that we will very soon be hearing it stated, as if it were established fact, that television causes autism.
In light of this, let me say up front that this entry probably should be more accurately titled “this article does not show that TV watching causes autism”. Read More...
