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One line from the CDC Autism Prevalence report you will likely never see quoted

28 Apr

The CDC came out with an autism prevalence estimate a few days ago. There have been a number of news stories on the subject and the usual attempts by credulous websites to use this to claim that vaccines cause autism.

It’s right there at the top, in the interpretations section of the abstract:

Because the ADDM sites do not provide a representative sample of the entire United States, the combined prevalence estimates presented in this report cannot be generalized to all children aged 8 years in the United States

The Age of Autism blog (as noted already, always a good place to look for people getting it wrong on autism) ran a piece “Breaking News: 1 in 59 children Born in 2006 have Autism, 1 in 36 between the ages of 3 and 17. What’s going on?” Because, you know, claiming an epidemic is in their mission statement.

SafeMinds, another organization promoting the failed “vaccine-induced-epidemic” idea of autism wrote:

Baltimore, MD, April 26, 2018 – SafeMinds, along with other national autism advocacy organizations, sent a letter today to Department of Health and Human Services (HHS) officials demanding a meeting within the next 30 days to discuss the creation of a Federal Autism Strategic Plan to address the nation’s autism crisis. The urgent letter follows the release of a report this afternoon by the U.S. Centers for Disease Control (CDC). The CDC report found that autism is now diagnosed in one in every 59 American children, representing 2 ½ times more autism in 12 years and a 15 percent increase in just two years.

First, there is an Autism Strategic Plan. A member of SafeMinds helped craft it with HHS while she was on the Interagency Autism Coordinating Committee. She voluntarily decided not to pursue another term on the IACC.

Second, your reason is that ” The CDC report found that autism is now diagnosed in one in every 59 American children”. The CDC told you explicitly in the first few paragraphs that can’t be said.

But I do appreciate that you are implying no epidemic among children. You clearly state that the rate is the same for all American children, not just the 8-year old children of the CDC study. Or did you miss that important point?

So, good luck with that letter. I’m sure your readership will not notice the problems with your logic, but HHS will.

There are more examples, but these make the point.


By Matt Carey

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Did autism prevalence increase by 20%? (answer: no)

28 Apr

The CDC came out with a new autism prevalence estimate yesterday. Their estimated autism prevalence is 1.68%.  That’s up from the estimate from 2 years ago (1.46%), but lower than a different recent study (2.76%).

I’m going to discuss some minor-league shenanigans.  It’s no surprise that some groups abuse facts and cherry pick data to make political points.  In this case it was useless.  there was no need to cherry pick.  I’ve done a lot of exposing the abuse of facts by some so-called autism advocacy groups.  I don’t get any joy from noting that people in my community are both dishonest and ignorant of science.  But much as that bothers me, it pales in comparison to the lost opportunities.  Millions of dollars were spent on this prevalence estimate alone, but all some groups do is dig for reasons to justify their “epidemic” story and push the long-ago failed idea that vaccines are to blame.

Over the years, news organizations and autism groups have jumped at the chance to put their spin on each new CDC autism prevalence estimate. Over the years I’ve spent a lot of time trying to unspin the takes of groups like the Age of Autism blog. AoA is, well…if you want to see autism done wrong, read the Age of Autism blog. Science, medicine, human rights and dignity, they can be counted upon to get things wrong.

With that in mind I decided the CDC announcement was a time to break my current trend of ignoring AoA. I literally haven’t read it in months. What I saw was both surprising and typical for them. Surprising in that they didn’t even bother to write their own pieces for the new prevalence numbers. Seriously–they just copied a couple of articles from other sites and left it at that.

By the way–this new low-level interest in autism prevalence appears to me to be a general trend–beyond just AoA. Autism is losing it’s status as having intense focus from the US media and public.  The chance to leverage the public’s interest into meaningul change is waning. That’s a far more interesting topic and far more important than this and I want to come back to it in the future.

So, what did AoA post? Big League Politics BREAKING: CDC Reports 20 Percent Autism Increase In Children and Breaking News: 1 in 59 children Born in 2006 have Autism, 1 in 36 between the ages of 3 and 17. What’s going on?. That first one caught my eye. First because in absolute terms, the autism prevalence increased by 0.22%. In relative terms, that’s about a 15% increase.  They could have said 15% and made their point, but why do that when 20% is even more scary?  More to the point–digging just a little into this 20% figure gives understanding that a true advocacy organization could use.

So how did they come to the idea that the autism prevalence increased by 20%? They skipped to page 13 and took one part of one paragraph out of context and, well, cherry picked. Completely unsurprising. They skipped over pages of data showing that we are failing to identify–and, therefore provide adequate services for–autistic minority children.

Sadly, AoA and their allies have spent over a decade denying this huge issue.   The reason is obvious: it doesn’t fit into the “vaccines cause autism” narrative.  So rather than push for better identification and better services for minorities, they’ve sacrificed these communities in for their political message.

It’s disgusting.

They didn’t dig any deeper into these numbers, even though the data were right in front of them. Also completely unsurprising. If they were the sort of people who dig into data and question, they wouldn’t be pushing the idea that vaccines cause autism.   Seriously.

Here’s the section they are relying upon:

Among the six ADDM sites completing both the 2012 and 2014 studies for the same geographic area, all six showed higher ASD prevalence estimates for 2012 compared to 2014, with a nearly 10% higher prevalence in Georgia (p = 0.06) and Maryland (p = 0.35), 19% in New Jersey (p<0.01), 22% in Missouri (p = 0.01), 29% in Colorado (p<0.01), and 31% in Wisconsin (p<0.01). When combining data from these six sites, ASD prevalence estimates for 2014 were 20% higher for 2014 compared to 2012 (p<0.01).

So, if you only pick the states where there were data in both this study (called 2014 because that’s when the data were collected to be analyzed) and the previous (2012) study, you get about a 20% increase (click to enlarge).

But what happens if you ask “why?”  As in, why do these states show a larger increase than the entire group?

I put some numbers in red and bolded them for emphasis. Those are states with lower than average autism prevalences. Take a moment to think about that–the states with low autism prevalences are showing larger prevalence increases than other states. Start with a low number, and you are bound to get bigger percentage increases.

Missouri, Colorado and Wisconsin started out with very low identification rates.  They’ve improved their identification rates. What if someone were to ask, “how did they do that?  Can we use that elsewhere to serve more unidentified autistic children?”

I’m sure the cherry-picking “let’s find a reason to fit this into the vaccines-cause-autism story” groups have already focused on New Jersey in the above figure.  New Jersey stands out–their autism rate increased by about 19% and they have a much higher autism prevalence rate. New Jersey also stands out for another reason: they aren’t lagging in identifying black or Hispanic autistic children:

In New Jersey, there was almost no difference in ASD prevalence estimates among white, black, and Hispanic children. Estimates for Asian/Pacific Islander children ranged from 7.9 per 1,000 (Colorado) to 19.2 per 1,000 (New Jersey) with notably wide CIs.

Wouldn’t it be great if someone were to say, “how did New Jersey close the gap in identifying some minority groups?”

Groups advocating for a better future for disabled people would do that.  People trying to keep the failed “it’s all vaccines fault” idea alive won’t.

Some people will be confused, and understandably so, at this point.  These are “autism prevalence” numbers.  Doesn’t that mean that this is a complete and accurate count of the number of autistic kids in each location?  No, they aren’t.  The people at the CDC are working hard and doing a good job with the information they have.  But this is a review of existing records, not a test of each individual kid.  The CDC have access to medical and/or school records (it varies by location what sort of records they have).

Keep in mind–the CDC autism prevalence numbers aren’t “these are the absolute accurate numbers for how many kids are autistic”. We are missing identifying kids. Doctors are missing autistic kids.  Schools are missing autistic kids. The CDC tries to make up for this by reviewing the records to determine which kids are autistic (i.e. they don’t just count existing diagnoses in the records–they “diagnose” from the records).  But they still miss kids in their counts. We need to get better. The fact that New Jersey isn’t leaving minority kids behind is huge.  The fact that lagging states are catching up is huge.

Doing things right–checking on numbers is hard. It takes time. AoA not only doesn’t take the time to be careful (which is typical for the “vaccines cause autism” groups), they know that it’s the simple message that scares people. “Autism increased by 20%”!!!! It may only take 5 minutes to actually dig and see what’s going on. But that’s five minutes most people don’t have time for.

Which is the long winded way to say:

A lie can travel halfway around the world before the truth can get its boots on

Groups like AoA live and breathe on taking advantage of that.  They were fake news long before the term was coined.

That said, I knew with the new autism prevalence numbers people would misuse them. It’s pretty obvious.  They’ve used that misinformation to drag parents into a world of guilt and shame for being part of vaccine injuries that, in at least the vast majority of cases, didn’t happen.  Even more, the autism-is-a-vaccine epidemic community had the resources for over a decade to make a real difference in the lives of autsitic people. As we watch autism fade a bit from the public’s view, it’s difficult to not cry a bit for the lost opportunity. It’s that, not their failed logic or twisted facts that is why I wrote the above.

By Matt Carey

Americans are still failing to identify and serve minority autistic children

27 Apr

The CDC recently published another autism prevalence study. It’s 23 pages long and has 26 authors, took 2 years to put together and no doubt cost millions of dollars. Out of that, the one fact from it that will be quoted is simply–the autism rate is now at 1.68%, or 1 in 59.

There’s so much more. But sometimes focusing on one simple message makes more impact than a lengthy analysis. So I’ll pick my own simple message (of my own):

we are failing to identify minority autistic children. And with that, we are failing to provide them the appropriate services and supports they deserve as citizens and residents of the U.S.

We can and we should do better.

Here is table 3 from the report:

The estimated autism prevalence for Hispanics is 1.4%. For Whites, it is 1.7%. Thousands of Hispanics and other minorities are being missed. Overall, thousands of autistic children, and many, many more adults, are being missed. But that’s another discussion.

By Matt Carey

If you are using California data to claim an autism epidemic, you’re doing it wrong. Or:The great anti-epidemic of intellectual disability in California.

22 May

If you’ve been reading about autism online, you have almost certainly read that autism “rates” are on the rise. But what if I told you that here in California intellectual disability has been dropping for over 20 years?

For many years the mainstay of the “autism is an epidemic” idea was the California Department of Developmental Services data. The CDDS keeps track of how many Californians are getting support under a number of specific disability categories. These data are publicly available (although not as easily available in the past), which makes them an easy source of data.

It’s easy to take a cursory look at the CDDS data and think “these are official data. Look at how much autism has increased!” Or claim “the CDDS only serves “severe” autism, there’s no way they were missed in the past.” You can even find a few publications to cite to back up these observations.

About a year ago I asked CDDS for some data. I hadn’t checked in a while and I wanted to see what trends are ongoing. Coincidentally, the Autism Society of San Francisco put out a report shortly after that: Autism Rising, A Report on the Increasing Autism Rates in California. So I was not alone in asking for data.  The Autism Society of San Francisco made the argument that the CDDS data are accurate and show an epidemic.

The Autism Society of San Francisco graph the data in many different ways, but the one that was closest to the way I was looking at the data was in Figure 5 (click to enlarge):

AS-SF Autism Rising Figure 5

and here is the caption for Figure 5:

Births of individuals later deemed to have DDS-eligible autism have been increasing sharply every year since the early 1980s. Typically intake into the system occurs between 2 and 7 years of age. The data reflects about 200 DDS autism births per year into the 1980s, but now the system is reflecting nearly 5,000 such births per year. The drop off in cases after birth year 2008 is likely attributable to usual delay in cases entering the system, and likely does not represent an actual decrease in DDS-eligible autism cases.

You can stop there and support your argument. And that’s just what most people do. Or you can question–how can I test if this is a “real” autism increase? For example, is the autism rate the same among different races? The answer is no. Is the autism rate the same in, say, San Francisco, Los Angeles, and Kern County? The answer is no. And there are many more questions one can ask of these data and over and over, the answer is no.

Either we aren’t counting all the autistics in our state, or there is something much more complex going on than vaccine, toxins, epigenetics, or whatever the claimed causes of the rise are. And I’ve gone through many of these discussions over the years. Let’s make this simple then. If one claims that the CDDS counts everyone within each disability category accurately and that the definitions they use aren’t changing with time, why is intellectual disability (mental retardation) dropping so fast in California?

You see I also graphed intellectual disability. I got autism counts, intellectual disability counts and “unduplicated” (total, each disabled person counted once) by birth year. I also got census data by birth year. And I graphed them. And anyone claiming CDDS data show an autism epidemic needs to do the same and to explain this graph, complete with the sharp peak for birth year 1993. (click to enlarge):

CDDS including ID

Intellectual disability has dropped. Off about 40% of the peak value.

If you think your idea for the rise in autism is correct, let’s take the failed vaccine idea as an example, you need to also explain how that resulted in far fewer people with intellectual disability. Plain and simple. And none of these claimed causes of an “epidemic” can explain the drop in ID.

Why bother challenging the people claiming an autism epidemic? Because it denies the existence of undiagnosed autistic adults. We have very little effort to identify those who were missed in past generations. And the likelihood is that these people–our people–are not being supported appropriately because of their misdiagnoses. And not only are we abandoning the misdiagnosed, we are failing to learn. What worked for past generations, the adults of today? What failed? What are the appropriate supports for the various needs of autistic adults? We don’t know today. And are unlikely to know by the time my kid is an adult, especially if we aren’t even looking at autistic adult needs today.

And then there’s the whole autism causation question. People spending their time trying to correlate CDDS data–data clearly confounded by numerous social influences–are unlikely to ever find a real answer.

But, for those who want to keep trying, include all the data. Give an explanation for this and you may be on to something.

CDDS including ID

By Matt Carey

U.S. announces 2% autism rate. Again. And it’s dependent on a change in the way a survey is worded. Again.

17 Nov

Last week a study was released showing an autism “rate” in the U.S. of about 2% (an estimated prevalence of 2.24% to be exact). Luckily one of the best science journalists out there focuses a lot of her attention on autism and covered this story. I’m writing of course about Emily Willingham and her article Increase In Autism Diagnoses Not An Increase In Autism.

The study in question is Estimated Prevalence of Autism and Other Developmental Disabilities Following Questionnaire Changes in the 2014 National Health Interview Survey. The abstract is at the bottom for those interested.

While other articles are discussing the large “increase in autism”. Or, as in this Reuters article, US autism numbers soar in which we read what must be a confusing message to many:

The results reflect a near doubling in autism rates over the past three years, but the US Centers for Disease Control, which released the data last week, says the shift is largely due to a change in the way the survey was worded.

Here’s the thing, before I saw what the study was, I actually thought that the discussion was about this study: Changes in Prevalence of Parent-reported Autism Spectrum Disorder in School-aged U.S. Children: 2007 to 2011–2012. In that study, released in 2013, a 2% autism “rate” was announced. And that was a significant change from the previous survey data (using the National Survey of Children’s Health). And like previous estimates based on survey’s the change is at least due in large part to a change in the way the survey was presented to parents (I’m looking for a link to the discussion of the change in survey questions that affected the 2013 estimate, but there was a shift and it had a big impact).

Thankfully much of the media, and even Autism Speaks, are pointing out how this 2% figure doesn’t represent a “real” change in autism prevalence, but is largely dependent on the study methods. Others can be counted on to shout “epidemic” and ignore some of the key reasons why this doesn’t reflect a real increase.

Number 1 reason–the autism prevalence is basically the same for kids who were 3-10 and kids who were 11-17:

AutPrevalence

A real increase would show up as a higher prevalence for younger kids.

One thing we see is a decrease in disparity for autism prevalence by race/ethnicity. African Americans have a slightly lower autism prevalence (it’s unclear whether this is statistically significant or not), and Hispanics have a decidedly lower autism prevalence (1.49% vs. 2.55% for Caucasians). Which means we still have far to go to identify and bring services to all autistics. And it also means that the autism prevalence estimates will continue to rise as we do identify more in under diagnosed populations.

AutPrevalence race-ethnicity

But let’s focus on the important part of that–we still have a large under-diagnosed/under-served population and it is largely among Hispanics. We really need to be focusing more attention on remedying that situation.

Here is the abstract for the current study:

Objectives—The developmental disabilities questions in the 2014 National Health Interview Survey (NHIS) were changed from previous years, including
question reordering and a new approach to asking about autism spectrum disorder (ASD). This report examines survey-based estimates of the lifetime
prevalence of ASD, intellectual disability (ID), and any other developmental delay (other DD) following the inclusion of a standalone ASD question, the
inclusion of specific diagnoses in the ASD question, and the ASD question preceding the other DD question, and compares them with estimates from
previous years.

Methods—In NHIS, one child is randomly selected from each family to be the subject of detailed questions on health conditions, functional limitations, and
health care utilization. Parents are asked if a doctor or health professional had ever told them that their child had each of a series of developmental disabilities.
Prevalence estimates of ASD, ID, and other DD for children aged 3–17 years were calculated using data collected in 2011–2014.

Results—The estimated prevalence of ASD based on 2014 data was 2.24%, a significant increase from the estimated annualized prevalence of 1.25% based on
2011–2013 data. In contrast, the prevalence of other DD declined significantly from 4.84% based on 2011–2013 data to 3.57% based on 2014 data. The prevalence of ID did not significantly change from 2011–2013 (1.27%) to 2014 (1.10%). The prevalence of having any of the three conditions was constant across survey years.

Conclusions—The revised question ordering and new approach to asking about developmental disabilities in the 2014 NHIS likely affected the prevalence estimates of these conditions. In previous years, it is likely that some parents of children diagnosed with ASD reported this developmental disability as other DD instead of, or in addition to, ASD. Following these changes, the 2014 ASD estimate was more similar to ASD prevalence estimates from other sources.


By Matt Carey

New study on inflammatory bowel disease and autism: Prevalence of Inflammatory Bowel Disease Among Patients with Autism Spectrum Disorders.

12 Aug

People with developmental disabilities often have additional medical issues at rates higher than the general population. For example, heart problems are more common in the Down Syndrome population and Timothy Syndrome. Hip dislocation is common among those in the Fragile X community. Mental health conditions and neurological disorders are very common in autistics (but somehow those are rarely mentioned in discussions of autism and comorbidities).

When it comes to autism parents online, perhaps the most talked about autism comorbidity is gastrointestinal disease. And, in specific, inflammatory bowel disease. This is a lasting legacy of Andrew Wakefield’s attempt to link the MMR vaccine and autism (an effort which set back work on autism and GI disease by a decade or more–see Blame Wakefield For Missed Autism-Gut Connection).

Mr. Wakefield’s assertion was that the MMR vaccine leads to a unique form of IBD (he dubbed it autistic enterocolitis, a condition which doesn’t appear to exist) and this somehow leads to autism. The model also asserts that autism rates have climbed with the introduction of the MMR in the UK (an argument that fails when when considers when the MMR was introduced in the U.S., but I digress). Given the Wakefield model, including the claim that the MMR has played a major role in the “autism epidemic”, we would expect a large fraction of autistics should have IBD.

With apologies to autistics with IBD for taking so long on this introduction–this all begs the question of what is the prevalence of IBD in the autistic population? Well, a recent study discusses this:

Prevalence of Inflammatory Bowel Disease Among Patients with Autism Spectrum Disorders.

Before we get to the prevalence let’s consider the important points. First–IBD does exist in autistics. Given communication issues and sensory issues, any medical condition is serious in the autistic population. Second–IBD is more prevalent in the autistic population. What this may say about the biology of autistics and the developmental trajectory is not discussed in the abstract of this study.

Finally let’s ask how big is the prevalence of IBD in the autistic population? The study looked at two sample populations. In one population 7 out of 2728 (0.26%) autistics had IBD. For another, 16 of 7201 (0.22%). Just because the prevalence is small doesn’t mean this isn’t an important issue for the autism communities. But, let’s face it, the claims of high and rising IBD prevalence in the autism community–the claims by Mr. Wakefield to support his attack on the MMR vaccine–are just not true. And, yes, this also means that people who think that all or most autistic kids should be treated for IBD are also not doing a service. Yes, treat people with IBD. But no, don’t assume autism = person with IBD.

The fact that IBD is not that common in autistics is not really that new. I recall the press conference for the MMR/autism study by Hornig et al.. One thing that slowed the study was the fact that there weren’t that many autistic kids whose symptoms really indicated the need for a colonoscopy. Contrary to some practitioners who seem to believe that all autistics should be ‘scoped.

Here’s the abstract from the study:

Background:
The objective of this study was to measure the prevalence of inflammatory bowel disease (IBD) among patients with autism spectrum disorders (ASD), which has not been well described previously.

METHODS:
The rates of IBD among patients with and without ASD were measured in 4 study populations with distinct modes of ascertainment: a health care benefits company, 2 pediatric tertiary care centers, and a national ASD repository. The rates of IBD (established through International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] codes) were compared with respective controls and combined using a Stouffer meta-analysis. Clinical charts were also reviewed for IBD among patients with ICD-9-CM codes for both IBD and ASD at one of the pediatric tertiary care centers. This expert-verified rate was compared with the rate in the repository study population (where IBD diagnoses were established by expert review) and in nationally reported rates for pediatric IBD.

RESULTS:
In all of case-control study populations, the rates of IBD-related ICD-9-CM codes for patients with ASD were significantly higher than that of their respective controls (Stouffer meta-analysis, P < 0.001). Expert-verified rates of IBD among patients with ASD were 7 of 2728 patients in one study population and 16 of 7201 in a second study population. The age-adjusted prevalence of IBD among patients with ASD was higher than their respective controls and nationally reported rates of pediatric IBD.

CONCLUSIONS:
Across each population with different kinds of ascertainment, there was a consistent and statistically significant increased prevalance of IBD in patients with ASD than their respective controls and nationally reported rates for pediatric IBD.


By Matt Carey

Kaiser Permanente starts the Autism Family Biobank Study

10 Aug

Kaiser Permanente has a long history of autism research. They’ve performed a number of epidemiology studies, including many on environmental risk factors and also the recent study on The health status of adults on the autism spectrum. They have recently embarked on a large study, the Kaiser Permanente Autism Family Biobank Study.

Sign up online
Study Flyer

You can also find picture books (social stories) for the sample donation process on the Autism Family Biobank website.

From the FAQ for the study, What is the KP Autism Family Biobank?

The KP Autism Family Biobank is a study of Kaiser Permanente Northern California children and young adults with Autism Spectrum Disorder (ASD) and their biological parents. The
study seeks to enroll 5,000 affected children plus their parents (for a total of 15,000 participants) to create a collection of genetic material and information for future research. Dr. Lisa Croen is the principal investigator of the study.

Autism genetics has turned out to be a very complex question. There’s no single “autism gene” but autism clearly has a large genetic component.

What does that mean in practical terms? We need a lot of data to understand the question of autism genetics. And that’s a big piece of what this study will do: bring a lot of data to bear. And not just genetic data. This is a key part of this study and can’t be stressed enough. Kaiser provides healthcare. They have electronic records on their patients. And these patients are the pool from which they will draw their study subjects.

Or to put it simply–they will be able to not only say, “these genes are associated with autism” but “these genes are associated with autism and low verbal skills, while these other genes are associated with autism and regression.” (to give a hypothetical example).

To do this they need a lot of people to participate. They are going to get 5000 autistic kids involved. And they won’t stop there: they will also include parents. That makes 15,000 participants. Not all genes are inherited. With the parents involved, Kaiser can can see if genes associated with autism are inherited or not.

Now many parents will ask (and it’s a valid question), “OK, what will this do for my kid?” It takes time (not a lot, but some) to participate and lots of kids don’t like doctor visits. But consider this: genetics helps people understand biology. With a better understanding of biology, one can make progress towards treatments. There’s a reason why some of the treatments proposed for autism came from research in Fragile-X. People have spent a lot of time studying this genetic condition and that focus has led to proposed treatments.

Or to put the short version of the message out–this isn’t just another genetics study. It’s bigger (15,000 people!) and brings a lot of value with the clinical data that Kaiser has. There’s a chance to have a big impact to better the lives of autistics. If you are a Kaiser member in the study area, please consider participating.

Links and recent news:

Sign up online
First KP Members Join Autism Family Biobank
Kaiser to look for autism’s causes in large-scale study
Study Flyer


By Matt Carey

Disclosure: I serve on a community advisory board for Kaiser. It is a volunteer position (I.e. I get no pay) and will not benefit from this study any more than anyone else in the autism community. And the decision to conduct this study was made before I became involved with Kaiser.