How Much is "The Most?" - the Volume of ABA Research

Back in 2003, Morton Gernsbacher published an interesting article that took applied behavior analysis (ABA) advocates to task for claiming that ABA is ‘scientifically proven.’   This upset some folks in the ABA community.   I liked it. 

It’s true that ABA studies have methodology limitations, like all studies of anything.   It was true when he wrote that there was less replication of these studies than there should have been.  That’s less true now, but more replication would still be good.  The standard for scientific proof is very high.   As advocates of science, advocates of ABA should take that standard seriously and talk about proof carefully.

What we can say with confidence is that ABA has the most evidence of effectiveness as an autism intervention.   There is no near competitor.   But how much is ‘the most?’   Gernsbacher says “It is to the great credit of ABA proponents that they have consistently sought to provide scientific evidence of the efficacy of their treatment.”  How much evidence amounts to ‘consistently?’ 

I sometimes describe myself as an autism ‘research junkie’ but I have to admit I haven’t read enough of the research to answer these questions.   I was sobered by the 2009 National Standards Report which reviewed 755 studies about autism intervention.   I counted in the bibliography – I had read only 22 of them.  So I have to take the word of the report authors, who say:

Approximately two-thirds of the Established Treatments were developed exclusively from the behavioral literature (e.g., applied behavior analysis, behavioral psychology, and positive behavioral supports).  Of the remaining one-third, 75% represent treatments for which research support comes predominantly from the behavioral literature. (p.52)

Do the math on the 519 studies in support of what they rate as Established Treatments and that adds up to 474 studies.  If you include the behaviorally based research in the Emerging Treatments (another 50), that’s a total of 524 studies cited in the report in support of ABA.  That’s a lot of reading.

How consistently ABA researchers have been publishing is even more amazing.   Most of the studies in the National Standards Report date since 1990.   What was happening before then?   In 1996, Johnny Matson of Lousiana State University published a review of the literature (here’s the abstract) of behavioral treatment for autism from 1980 to 1995.   He detailed the results of 251 studies.    Matson also cites an earlier review  that describes another 200 treatment studies in the 1970s and 100 more in the 1960s.   

So that’s 50 years of constantly growing research and a total number of studies closing in on 1000.   We can’t say ‘proven,’ I agree.   But we can say the volume of evidence is impressive indeed.