Monday, February 02, 2009

Revisiting the costs of autism

ResearchBlogging.org
Michael Ganz of Harvard has published two papers about the costs of autism, a book chapter in 2006 and a peer-reviewed paper in 2007. Media attention followed, including a 2007 Globe and Mail story under the headline "Autism a lifelong burden, study shows."

Dr Ganz's work was embraced by leading autism advocates in Canada, as evidence that unlimited ABA-based autism interventions must be funded by governments, or else staggering costs to society will ensue. Here is leading autism advocate Harold Doherty, writing in 2007 in response to Dr Ganz's work:

"In Canada the courageous parents who litigated the Connor Auton case started telling government over a decade ago that the financial burden to society down the road would be tremendous if early ABA intervention was not provided intensively right away and funded."
Here is Senator Jim Munson, leading autism advocate, as reported by CBC, also in 2007:

"Not providing ABA treatment is more expensive because it involves respite care, group homes and institutionalization, said Munson, who referred to a Harvard University study that put the annual cost of autism to Canada's economy at $3.5 billion."
Senator Munson again, from a 2007 speech:

"A recent study by Harvard University demonstrates that each child in the U.S. with autism will cost society about $3.2 million in medical and non-medical costs over his or her lifetime [1]. With the rising number of diagnoses of autism, the eventual costs will be staggering. We're in a situation where spending on treatment, even expensive treatment, is actually a savings."
The footnote [1] is to Dr Ganz's 2006 book chapter, and the sole treatment referred to by Senator Munson, as "proven to work," is ABA-based intensive intervention.

FEAT in Canada, which is also called "Medicare for Autism Now," is a powerful autism advocacy lobby group. FEAT demands that Lovaas-type ABA be mandated as medically necessary treatment for autism under the Canada Health Act. Here is FEAT in 2008:

"AUTISM is a North American health care epidemic of staggering proportions... The costs to the Canadian economy of NOT treating autism is $3.5 billion a year... the cost in human suffering is immeasurable."
While FEAT makes no direct reference to Dr Ganz's work, the $3.5 billion figure does not come from any existing Canadian study. According to the CBC, Senator Munson also used this figure and attributed it to Dr Ganz, and indeed this figure shows up in the Globe and Mail story about Dr Ganz's work that I referred to above. Dr Ganz's published work about the costs of autism does not make any mention of Canada, but Canada's leading autism advocates have apparently embraced an estimate based on Dr Ganz's US work and published only in a newspaper.

In any case, the premise of these leading Canadian autism advocates is the same. First, they use Dr Ganz's work as an occasion to unscientifically deny the existence of older autistics. Like many autism advocacy signature positions, this is an excellent way to ensure that many autistics will have very difficult lives and will be unlikely to have good outcomes. But Dr Ganz's work, if you read it, assumes a high, stable rate of autism.

Second, leading Canadian autism advocates cite Dr Ganz's work as evidence that government funding for ABA-based autism interventions is the only way to avoid the staggering costs of autism.

In the paper reporting his methodology, Dr Ganz does write about the costs of behavioural interventions for autism. From the "Behavioral Therapies" section of Ganz (2006):

"Although it is not completely clear how effective different types of behavioral interventions are for children with autism, it is rather well accepted that some type of intervention should be initiated. Because their use is becoming more pervasive and as more states are legislating that behavioral therapies become covered services as part of health insurance plans, their costs are included here."
Then Dr Ganz goes on to describe the possible benefits of these interventions:

"However, as the estimates of effectiveness, and hence the financial and nonfinancial benefits, are controversial and because the correspondence between improvement in symptoms and the costs of these interventions are not clear, only the costs of the intervention are enumerated here and are not offset by potential benefits."
Dr Ganz provides a range of references to support the above statements. The upshot is that according to Dr Ganz's model, existing evidence for the effectiveness of behavioural interventions in autism is insufficient for any conclusion that these interventions have benefits, financial or otherwise. Instead, there is only sufficient evidence to conclude that these interventions have costs. This is the model on which Dr Ganz's 2007 paper is based, as is directly stated in the paper.

So autism advocates who promoted Dr Ganz's work about the costs of autism in reality promoted a study whose author concluded that the effectiveness of ABA-based autism interventions has not yet been established, such that no benefits for this kind of intervention can be claimed. As often happens, the question arises as to whether autism advocates read the study and misrepresented it, or did not bother to read it and made public claims about it anyway. Those who are not enamored with autism advocacy standards, and who are genuinely concerned about the future of autistics, will take the trouble to read the primary sources and will draw their own conclusions.


References:

Ganz, M. (2006). The costs of autism. In S.O. Moldin & J.L.R. Rubenstein (Eds.), Understanding Autism (pp. 475-502). Boca Raton FL: Taylor & Francis.

Ganz, M. (2007). The lifetime distribution of the incremental societal costs of autism. Archives of Pediatrics and Adolescent Medicine, 161, 343-349