Monday, June 15, 2009

Notes on autism severity and the DSM-V

I was asked briefly to comment on the notion of "severity" of autism as currently proposed for the DSM-V. Here are some far from complete notes (some from earlier writing or work of mine) I organized in response:

Currently, “severity” of autism most often refers to the attempt to quantify the obviousness of autistic traits and abilities. The more obvious these traits and abilities are judged to be, and therefore the more atypical a person is judged to be, the more “severe” autism is considered to be.

Being “more severe” (having more obvious autistic traits and abilities, or being more obviously atypical) is widely presumed to be worse than being “less severe” (having less obvious autistic traits and abilities or being less obviously atypical), while being not autistic at all (no obvious autistic traits and abilities) is considered an “optimal outcome.”

However, there is no current consensus on what neurocognitive differences underlie observable autistic atypicalities and therefore fundamentally define what makes a person autistic rather than nonautistic. At this fundamental level (what autism is), there is currently no consensual way to judge who is “more autistic” or “less autistic” (which would be construed as “more severely autistic” and “less severely autistic”) or whether this would be good, bad or irrelevant.

Currently there is/are no consensual instrument(s) agreed to measure autism “severity.” The major diagnostic instruments (ADOS, ADI-R) do not work like scales, though they have often and misleadingly been misapplied this way. A recent preliminary attempt to transform the ADOS into a scale of “severity” has just been published (Gotham et al., 2009).

On popular measures of “severity” (the CARS, the ADI-R improperly used as a scale, the SRS), an autistic who has one or more very high apparent abilities (that is, has a highly uneven profile of apparent abilities) will score as more "severe" than an autistic whose apparent abilities are uniformly low.

The large proportion of autistics recently reported to have exceptional skills (Howlin et al., 2009) would be judged as less “severe” if they lost those skills. Exceptional skills are considered to increase “severity” (that is, atypicality) in autism, not decrease it. This would also likely be true of autistic cognitive strengths which have been revealed in the peer-reviewed literature in comparisons between the performance of autistics and nonautistics on a wide range of tasks (I have started compiling an inventory of these, which was the subject of an IMFAR 2009 poster). Indeed, at IMFAR 2009, the loss of exceptional autistic abilities (Eigsti et al., 2009; from Deborah Fein’s group) was reported as evidence for “optimal outcomes” in autism.

In the same direction, we have found that autistics who scored higher on pieces of the ADI-R (and would therefore commonly be assumed to be "more severe") had a wide range of better visual skills than autistics who scored lower on these measures (Caron et al., 2006).

Perhaps unsurprisingly then, autism “severity” (defined and measured in various ways) has been a poor predictor of outcomes in autism (Howlin, 2005). Here are two examples from papers reporting very good outcomes in autism:

It cannot be emphasized strongly enough that… it would have been impossible for anyone to predict this outcome. (Kanner et al., 1972)

… early history explained little of the variance in outcome. Indeed, the good and poor outcome groups differed little with respect to early impairments in social responsiveness, deviant language, and bizarre behaviors. (Szatmari et al.,1989)
Currently the best adult outcomes reported in the literature still belong to autistics who as children met the narrowest, strictest, and presumed-to-be most “severe” autism diagnostic criteria ever devised (Kanner et al., 1972; Szatmari et al., 1989; Farley et al., 2009). Asperger (1944/1991) described an individual whose outcome was outstanding (he was a successful academic) as “grossly autistic” with “impossible behavior,” etc.

Some of the most obvious (that is, most “severe”) and successful autistics have been and continue to be individuals regarded as autistic savants. Indeed, the “obviousness” of these individuals, the fact that their atypicalities are so obvious (which would be judged as so “severe”), has been successfully exploited in the autism literature as a means of investigating the fundamental atypicalities which make autistics autistic.

The assumption that having more obvious autistic traits and abilities is bad (“more severe”) has resulted in prejudicial judgments in the literature. An autistic boy (who has accomplished more as a child and young adult than most people, autistic or otherwise) with a full-scale IQ of more than 100 and a strong performance on numerous tests is judged to be “low-functioning,” because he is so obviously atypical. That is, he is judged to be very “severely” autistic (Bonneh et al., 2008; Belmonte et al., 2009), and this must solely be a very bad thing. In Aldred et al. (2004), preschool autistic children are falsely judged to be “low-functioning” or “high-functioning” solely on the basis of presumed autism “severity” falsely drawn from ADOS scores. It is being falsely and prejudicially assumed that an autistic whose traits and abilities are more obvious must function poorly.

The proposed DSM-V changes will enhance societal prejudices against autistic traits and abilities. These prejudices already serve to prevent autistics whose traits and abilities are more obvious from being considered able to learn, to communicate, to make decisions about our lives, to walk around freely, to be employed, etc. Under the proposed DSM-V changes, autistics who are highly and obviously atypical would be even more harshly judged, without there being anything approaching a sufficient empirical rationale for this. Autistics whose communication and social interaction is highly atypical, or who most strongly pursue their focused abilities and interests (something which has widely been acknowledged leads to good outcomes, but has largely not interested researchers; Howlin, 2005), will now be at risk of being regarded as “most severe.” This is at a time when the term “severe autism” is popularly equated with low expectations, hopelessness, dread and horror.

Also, in my experience, the term “severe autism” is commonly used as a justification for why autistic people not only can but must be treated in ways that would be instantly recognized as unacceptable in any other population. This includes lowering or discarding very basic standards of science and ethics, a pervasive practice now applied to the entire autistic population. I am referring to the basic standards of science and ethics that automatically protect and benefit nonautistics, and without which they could not proceed safely in society, much less have good outcomes.

The proposed DSM-V wording raises numerous specific concerns; I will mention two. One is that it enshrines the false and harmful assumption, an assumption showing a striking absence of reciprocity on the part of the DSM-V committee, that if autistics communicate or interact in atypical and possibly very adaptive ways, then this communication or interaction must be defective or wrong, or must not exist at all. Another concern is that by using words such as “rituals,” the DSM-V is perpetuating the misconstrual of autistics’ focused abilities and interests (and motor mannerisms). This misconstrual led to the demonstrably false and harmful assumption that autistics’ atypicalities in this area amount to “obsessions” and must be treatable in the same manner as OCD (see recent failed citalopram RCT, King et al., 2009; a failed fluoxetine RCT has been announced by Neuropharm and Autism Speaks, but not published yet).

In these and other ways the proposed DSM-V autism criteria define possibly very adaptive but atypical autistic traits and abilities as being more “severe” (worse or more defective) the more they are obvious. This leads to the assumption that such traits and abilities should ideally be suppressed and eliminated.


Aldred, C., Green, J., & Adams, C. (2004). A new social communication intervention for children with autism: pilot randomised controlled treatment study suggesting effectiveness. Journal of Child Psychology and Psychiatry, 45, 1420-1430.

Asperger, H. (1944/1991). 'Autistic psychopathology' in childhood (Frith, U., Trans.). In: Frith, U. (Ed.), Autism and Asperger Syndrome. Cambridge University Press, Cambridge, UK, pp. 37-92.

Belmonte, M.K., Bonneh, Y.S., Adini, Y., Iversen. P.E., Akshoomoff, N.A., Kenet, T., Moore, C.I., Simon, H.J., Houde, J.F., & Merzenich, M.M. (2009). Autism overflows with syntheses. Neuropsychology Review, 19, 273-4.

Bonneh, Y.S., Belmonte, M.K., Pei, F., Iversen, P.E., Kenet, T., Akshoomoff, N., Adini, Y., Simon, H.J., Moore, C.I., Houde, J.F., & Merzenich, M.M. (2008). Cross-modal extinction in a boy with severely autistic behaviour and high verbal intelligence. Cognitive Neuropsychology, 25, 635-52.

Caron, M.-J., Mottron, L., Berthiaume, C., & Dawson, M. (2006). Cognitive mechanisms, specificity and neural underpinnings of visuo-spatial peaks in autism. Brain, 129, 1789-802.

Farley, M.A., McMahon, W.M., Fombonne, E., Jenson, W.R., Miller, J., Gardner, M., Block, H., Pingree, C.B., Ritvo, E.R., Ritvo, R.A., & Coon, H. (2009). Twenty-year outcome for individuals with autism and average or near-average cognitive abilities. Autism Research, 2, 109-118.

Gotham, K., Pickles, A., & Lord, C. (2009). Standardizing ADOS scores for a measure of severity in autism spectrum disorders. Journal of Autism and Developmental Disorders, 39, 693-705.

Howlin, P. (2005). Outcomes in autism spectrum disorders. In: Volkmar, F.R., Paul, R., Klin, A.,Cohen, D. (Eds.), Handbook of Autism and Pervasive Developmental Disorders (pp. 201-220). Hoboken, NJ: Wiley.

Howlin, P., Goode, S., Hutton, J., & Rutter, M. (2009). Savant skills in autism: psychometric approaches and parental reports. Philosophical Transactions of the Royal Society B: Biological Sciences, 364, 1359-1367.

Kanner, L., Rodriguez, A., & Ashenden, B. (1972). How far can autistic children go in matters of social adaptation? Journal of Autism and Childhood Schizophrenia, 2, 9-33.

King, B.H., Hollander, E., Sikich, L., McCracken, J.T., Scahill, L., Bregman, J.D., Donnelly, C.L., Anagnostou, E., Dukes, K., Sullivan, L., Hirtz, D., Wagner, A., & Ritz, L. (2009). Lack of efficacy of citalopram in children with autism spectrum disorders and high levels of repetitive behavior: citalopram ineffective in children with autism. Archives of General Psychiatry, 66, 583-590.

Szatmari, P., Bartolucci, G., Bremner, R., Bond, S., & Rich, S. (1989). A follow-up of high-functioning autistic children. Journal of Autism and Developmental Disorders, 19, 213-225.