Will the DSM-5 Reduce Rates of Autism?
Yes, by a lot and for the wrong reasons.
Posted Nov 20, 2012
There has been a heated controversy about the DSM-5 proposal to redefine autism. Will its dramatic changes in definition result in dramatic changes in who gets diagnosed and will this cause a big reduction in the overall rate of autism? The DSM-5 folks claim their changes will have minimal impact. My prediction has been that they will have a major impact.
Dr. Lynn Waterhouse, an autism researcher for more than thirty years, has weighed in on the issue in her recently published book, Rethinking Autism: Variation and Complexity. Dr. Waterhouse believes the DSM-5 criteria are seriously flawed and will reduce the number of diagnoses. She sent this email:
"Dr. Catherine Lord, head of the DSM-5 autism group, recently cited a data analysis she performed as conclusive evidence that DSM-5 criteria for Autism Spectrum Disorder (ASD) will "not change the number of children with clinical diagnoses."
I disagree. First off, Dr Lord did find that using the new DSM-5 criteria caused about a 10% reduction in ASD diagnoses. That's a lot of kids who will no longer qualify for the diagnosis and who will not get services.
And Dr Lord's 10% estimate is almost certainly way too low because two of her study's three data sets were not really representative of the typical children assessed for ASD. It is a very good bet that her results won't generalize very accurately to real world settings where a much larger percentage of kids would lose the diagnosis.
Other (admittedly smaller) studies tell a radically different story- one that should inspire a lot more caution in the DSM-5 group than it has. Mattila found only 46% of those given a DSM-IV diagnosis met criteria for DSM-5 ASD. Taheri and Perry found only 63% of DSM-IV patients met DSM-5 criteria. And McPartland found only 60% diagnosed with ASD under DSM-IV would get a DSM-5 ASD diagnosis.
The DSM-5 criteria define ASD with two core symptoms: (1) global impairment in social communication and social interaction not accounted for by developmental delay; and, (2) a restricted, repetitive pattern of behavior, interests, or activities.
Worley and Matson compared 78 children given a DSM-5 ASD diagnosis with 52 children who met DSM-IV but not DSM-5 ASD criteria. Surprisingly, they found no significant differences in overall autism symptoms between the two groups. Mandy found that 64 of 66 individuals with a DSM-IV diagnosis of Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) would be excluded from a DSM-5 ASD diagnosis because none of the 64 met the second DSM-5 criteria—restricted repetitive behaviors, interests, or activities—even though all 64 had global impairment in social communication and social interaction. Mayes, Black and Tierney found only 27% of children with PDDNOS were identified as having ASD with the DSM-5 criteria.
These and other independent research groups have reported that DSM-5 ASD criteria will significantly reduce the number of ASD diagnoses. Their findings counter Dr. Lord's claim that DSM-5 ASD criteria will not change the number of people diagnosed. Because nearly all of those excluded from a DSM-5 diagnosis have serious developmental social interaction impairment, they cannot be correctly diagnosed by any of the other DSM-5 childhood disorders, such as Social Communication Disorder or Intellectual Developmental Disorder. These children will need services that will be more difficult to obtain without a DSM-5 diagnosis. Unfortunately, the DSM-5 group has chosen to simply ignore data that don't conform with its beliefs."
Thanks, Dr Waterhouse. The DSM-5 autism group has been blinded by an intellectual conflict of interest. Eager to introduce its concept of an autism spectrum, the group somehow lost sight of a crucial and obvious fact- its proposed criteria set is written so exclusively that it must inevitably reduce the diagnosis of autism.
I personally believe that autism is currently being over diagnosed because it has been too closely coupled to school services. I am all for providing needed school services but am very much against flawed and sloppy psychiatric diagnosis. We should as a society get kids the services they need without tagging many of them with an inaccurate diagnosis that can sometimes haunt their lives with a stigmatizing and damaging (mis)label.
But I don't think the needed reduction of rates should come from a mistake in DSM-5 criteria writing or the over valuation of one study that has been conducted by the person who is most responsible for recommending the change. This question is clearly far too important to be left to a very small group of biased experts who ignore contrary data and opinion. It deserves the kind of independent scientific review that was requested by fifty-one mental health associations, but denied by the APA. Changes this big should not be based on the beliefs of a few using data that is so contested.
Huerta, M., Bishop, S., Duncan, A., Hus, V., & Lord, C. (2012). Application of DSM-5 criteria for autism spectrum disorder to three samples of children with DSM-IV diagnoses of pervasive developmental disorders. American Journal of Psychiatry, 169, 1056–1064.
Kupfer, D. J., & Regier, D. A. (2011). Neuroscience, clinical evidence, and the future of psychiatric classification in DSM-5. American Journal of Psychiatry, 168, 672–674.
Mandy, W. P. L., Charman, T., & Skuse, D. (2012). Testing the construct validity of proposed DSM-5 criteria for autism spectrum disorder. Journal of the American Academy of Child and Adolescent Psychiatry, 51, 41–50.
Mattila, M. L. et al. (2011). Autism spectrum disorders according to DSM-IV-TR and comparison with DSM-5 draft criteria: an epidemiological study. Journal of the American Academy of Child and Adolescent Psychiatry, 50, 583–592.\
Mayes, S. D., Black, A., & Tierney, C. D. (2013). DSM-5 under-identifies PDDNOS: Diagnostic agreement between the DSM-5, DSM-IV, and Checklist for Autism Spectrum Disorder. Research in Autism Spectrum Disorders, 7, 298-306.
McPartland, J. C., Reichow, B., & Volkmar, F. R. (2012). Sensitivity and specificity of proposed DSM-5 diagnostic criteria for autism spectrum disorder. Journal of the American Academy of Child and Adolescent Psychiatry, 51, 368–383.
Taheri, A., & Perry, A. (2012). Exploring the proposed DSM-5 criteria in a clinical sample. Journal of Autism and Developmental Disorders, 42, 1810-1817.
Worley, J. A. & Matson, J. L. (2012). Comparing symptoms of autism spectrum disorders using the current DSM-IVTR diagnostic criteria and the proposed DSM-5 diagnostic criteria. Research in Autism Spectrum Disorders, 6, 965-970.