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Autism Diagnosed With a Fifteen Minute Brain Scan
kkleiner writes "A new technique developed at King's College London uses a fifteen minute MRI scan to diagnose autism spectrum disorder (ASD). The scan is used to analyze the structure of grey matter in the brain, and tests have shown that it can identify individuals already diagnosed with autism with 90% accuracy. The research could change the way that autism is diagnosed – including screening children for the disorder at a young age."
Counting the number of first posts you get on slashdot
MRIs are expensive, and autism-like behavior is obvious enough that you can narrow down the group of people you're going to test significiantly before you start testing. Also, for families with one or more kids with behavioral disorders, a 15-minute test usually doesn't qualify as "stress", at least not compared to all the other crap they have to go through.
its actually much higher than that. What you're quoting is that 1 in 10 people with autism and given a false negative. Its actually much worse. Out of 10,000 children, 1980 would be found positive, out of which only 90 would have the disease. So only about 5% of people who tested postive would actually be autistic. It says this in TFA.
So it only has a 4.5% true positive rate. Great.
With Autism being so prevalent in humans you do have to wonder if it is really a disease or mistake, or perhaps either a previous evolutionary step or our next evolutionary step. While people who suffer at the extreme ends of the autistic spectrum would have difficulty maintaining a society, some of the more moderate autistic individuals are leaders in engineering, technology, and science. I do worry that when you diagnose someone with autism there is this natural "I'm broken" feeling along with it, and everyone treats you like you're disabled and thus useless. So I cannot say if being able to identify autism more often is a good or bad thing.
It is interesting, but unsurprising, that they found that ADHD and autism had no link thus far. Based on the symptoms I expect we'll find that if ADHD exists at all that it will be localised around control, while autism is localised around right/left brain communication.
As you said, this will just be used for further testing. Treatment for autism is very similar for other behavioral abnormalities, so not much will change for the families. If a child has already been singled out for further testing by their teachers/counselors/doctors/family, this will just be another in a set of tests to help further treatment. A child with EBD or Autism receives much of the same interventions at school and home. The interventions are extremely specific to each child; knowing that this child may be autistic gives parents, teachers and doctors a more focused approach to treatment. It directs which bag-of-tricks to start working from. Fortunately, if the child is not actually autistic, but has say Pervasive Development Disorder (PDD), many of the same interventions such as remedial communication skills and socialization skills can be used.
It's not like this test puts a kid into a box with only one possible medication or treatment is offered. Each child's treatment is developed with the parents, teachers and other professionals. Some kids need headphones to walk though the cafeteria, some kids need a special squeeze ball, some kids need slow subtle introductions to complex social situations with highly scripted encounters to help them understand what is going on. This is true for the whole spectrum of EBD/autism disorders. Being able to scan a kid that might be autistic just gives everyone a much better starting place. They have a greater chance of successful treatment if they know which bag to start with rather than just grasping at straws.
This one's tricky. You have to use imaginary numbers, like eleventeen... --Hobbes
The research could change the way that autism is diagnosed - including screening children for the disorder at a young age.
The thing about primary screening tests is that they have to give false positives, due to high sensitivity and lower specificity. It's ok if the test tells you you have HIV when actually you don't. It's NOT ok if it doesn't tell you you have it when you do. The other thing about primary screening tests is that they have to be cheap. This test is far from cheap and in fact consumes limited resources. In some countries there are waiting lists for MRIs.
Perhaps this test could be used as a secondary screen, if specificity can be proven to be high enough, to screen those doubtful or borderline cases so that they can be correctly diagnosed.
Seven puppies were harmed during the making of this post.
Then I must have Asperger's too. I don't go to church, I don't watch sports on TV, I believe that men went to the moon, I believe that heavy use of fossil fuels is causing global warming, and I believe fluor is good for your teeth.
Maybe I was vaccinated when I was a kid.
Therapy's not humiliating. Hell, OT's kinda fun.
Real humiliation is when you're growing up and all the interactions with your peers blow up in your face due to your mind-blindless and inability to read body language or understand personal space, and your classmates ostracize you because they think you're weird, and you don't know what's going wrong. And since there's nothing you know of (because your'e undiagnosed) that differentiates you from your peers or explains why this is happening, you conclude you're getting ostracized because you're some doofy, idiotic, bad person. That, my friend, is real humiliation.
Sounds like every episode of House.
Not really -- the problem is with the base rate fallacy. Suppose that there's a test that will tell you whether or not you have a disease with 99% accuracy: if you have it, you're 99% likely to test positive; if you don't have it, you're 99% likely to test negative.
Now, you get a test and it's positive. What's your probability of having the disease?
The answer is, "There's not enough information to answer the question." The missing piece of information is the "base rate".
Suppose that 50% of the people have the disease. Then in testing 1 million people, 500K will have the disease, of which 495K will come back positive (true positive), and 5K the test will come back negative (false negatives). 500K will not have the disease, of which 495k will come back negative (true negative), and 5k will come back positive (false positive). If the test came back positive, you're either a true positive or a false positive. Since there are 500K positives, and 495K of those are true positives, your chances of having the disease are 99%.
Suppose instead that 1% of people have the disease. Then in testing 1 million people, 990K will not have the disease, and 10K will have it. Of the 990K, 980K will come back negative (true negative) and 10K will come back positive (false positive). Of the 10K, 9900 will come back positive (true positive), and 100 will come back negative (false negative). There are 19,900 who tested positive, of which only 9900 (less than half) actually have the disease. So if you tested positive, your chances are about 50%.
So even if the test itself is very accurate (and I think 99% is pretty accurate), if the base rate is low enough (and in autism I believe it's still less than 1%), a positive reading may not be conclusive. You'd have to correlate it with other symptoms to make sure.
TCP: Why the Internet is full of SYN.
read "Why autism can't be diagnosed with brain scans" at http://www.guardian.co.uk/science/blog/2010/aug/12/autism-brain-scan-statistics