Thursday, November 09, 2006

Autism advocacy and aversives (part two)

In her book "Science for Sale in the Autism Wars" (p68), Sabrina Freeman states that only four of the 19 experimental group autistic children in Lovaas (1987) received a treatment including physical aversives, thus minimizing their role in this landmark study. As often happens with statements from Canada's leading autism advocates, it's impossible to say whether Dr Freeman is unfamiliar with the scientific literature, or is familiar with it and is misrepresenting it.

Lovaas (1987) identifies "a slap on the thigh" (along with "a loud 'no'") as part of the treatment for the 19 autistic children in the experimental group, but not for the 19 autistic children in Control Group 1, in his main experiment. By his "main experiment", I mean the non-randomized controlled trial with the celebrated 47% rate of "normal functioning" as its experimental group's outcome. This use of aversives is reiterated in Lovaas and Smith's (1988) more detailed description of the study reported in Lovaas (1987).

However, as I've previously written, Dr Lovaas also took measures to demonstrate that this "aversive procedure", as Dr Freeman puts it in her book, was an effective and indeed essential component in the treatment received by the 19 experimental group children. This involved what Dr Lovaas called a "within-subjects replication design", in which the use of physical aversives was manipulated in four children from the experimental group and four from Control Group 1. This study-within-a-study is reported to be a success:

During baseline, when the contingent-aversive component was absent, small and unstable reductions were observed in the large amount of inappropriate behaviors, and similar small and unstable increases were observed in appropriate baheviors such as play and language. These changes were insufficient to allow for the subjects' successful mainstreaming. Introduction of contingent aversives resulted in a sudden and stable reduction in the inappropriate behaviors and a sudden and stable increase in appropriate behaviors. (p7)

Dr Lovaas concludes, about contingent aversives, that

...at least one component in the treatment program functioned to produce change, which helps to reduce the effect of placebo variables. (p7)

And,

...the within-subjects study showed that at least one treatment component contributed to the favorable outcome in the intensive treatment (experimental) group. (p8)

And further:

In the within-subjects studies that were reported, contingent aversives were isolated as one significant variable. Therefore, it is unlikely that treatment effects could be repeated without this component. (p8)

Two other papers from Dr Lovaas' group from around the same time (Epstein et al., 1985, which reports on 6 of the 19 experimental group children; and Lovaas et al., 1987, which describes part of the study-within-the-study) also refer to the importance of contingent aversives in the study design and findings which were later reported in Lovaas (1987).

The literature leaves no doubt that all 19 autistic children in the experimental group in Lovaas (1987) were subject to contingent aversives. There's also ample evidence that this "treatment component" was, in a separate experiment involving 4 experimental and 4 control group children, found then argued to be essential in achieving the famous result in the main experiment in Lovaas (1987). Dr Freeman's misreporting of the literature serves her purpose, in dismissing as "spurious" any concerns about aversives. But it also exemplifies the disrespect our most important autism advocates have for peer-reviewed science.

In fact, there's a later ABA intervention study from UCLA in which only four autistic children in an experimental group were subject to contingent aversives, but Dr Freeman does not mention this study or reference it in her book. That's going to be part three.


References:

Epstein, L.J., Taubman, M.T., and Lovaas, O.I. (1985). Changes in self-stimulatory behaviors with treatment. Journal of Abnormal Child Psychology, 13, 281-294.

Freeman, S.K. (2003). Science for sale in the autism wars. Lynden, WA: SKF Books.

Lovaas, O.I. (1987). Behavioral treatment and normal educational and intellectual functioning in young autistic children. Journal of Consulting and Clinical Psychology, 55, 3-9.

Lovaas, I., Newsom, C., and Hickman, C. (1987). Self-stimulatory behavior and perceptual reinforcement. Journal of Applied Behavior Analysis, 20, 45-68.

Lovaas, O.I., and Smith, T. (1988). Intensive behavioral treatment for young autistic children. In B.B. Lahey, and A.E. Kazdin (Eds.), Advances in Clinical Child Psychology, 11. New York: Plenum Press.

4 comments:

mcewen said...

Thank you for researching the research. I doubt if I would have been capable of reading the entire 'clinical' original.
Best wishes
http://whitterer-autism.blogspot.com

Michelle Dawson said...

Hi McEwen, you're welcome! Mostly, I like reading research, though the content can sometimes be very hard to take. Even so, I prefer to get it from the original source.

Jannalou said...

I like reading non-fiction. The problem comes when things are presented as fact when they are nothing of the sort.

I really appreciate the time and effort you take to go through these things and try to make sense of them - even though it's really difficult to make sense of people sometimes. (We're so irrational...)

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