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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
What are the operators of these machines called technically? Shamans?
They are probably psychiatrists--pretty much the same thing as shamans.
Say you scan 50,000 a year, you'll get 5000 false positives. That means each year you'll have 5000 children who'll have to go through humiliating therapy and have their education severely hampered for no good reason! Of those 50,000, you'd expect only 500 to actually have autism.
Even if you used this as a basis for further testing, You're still putting 10 families through the stress of comprehensive testing for autism for no reason for every 1 family whose child actually has the condition.
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.
I can only see this as a good thing, I'm on a compsci course and as you'd expect it seems like a good third of the people there claim to have aspergers, most of those seem fairly typical and reasonably socially functional. I'd be *highly* interested to see what this test reveals about them. This isn't to say I don't believe in the condition, I know plenty who have it and exhibit obvious major behavioural patterns and have actual issues with such things, I for one just suspect it's *way* over diagnosed, hell a number of psychiatrists have called me "aspie" after 5 minutes of talking to me, I certainly don't buy it. I just hope this sort of screening will help people who actually need help get the care they need and de-clog the system of hypochondriac nerds who want to feel special.
Since the main article says exactly that, how can it be inaccurate?
The Tao of math: The numbers you can count are not the real numbers.
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.
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.
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
Technologists, actually. It's the ones who READ the tea lea...err, brain scans who are the shamans, not the ones who do them. Beware of radiologists with bones through their noses.