Saturday, May 29, 2010

Interesting New Study

Liu, King,& Bearman have published a fascinating new epidemiological paper.

Here is the abstract:

“Despite a plethora of studies, we do not know why autism incidence has increased rapidly over the past two decades. Using California data, this study shows that children living very close to a child previously diagnosed with autism are more likely to be diagnosed with autism. An underlying social influence mechanism involving information diffusion drives this result, contributing to 16% of the increase in prevalence over 2000-2005. We eliminate competing explanations (i.e., residential sorting, environmental toxicants, and viral transmission) through seven tests and show that information diffusion simultaneously contributed to the increased prevalence, spatial clustering, and decreasing age of diagnosis.”

I cannot offer firm opinion based on the abstract alone, but I would be somewhat skeptical as to how well they could account for residential sorting, environmental toxicants, and viral transmission. However, I will reserve criticism until I can read the study in full.

On the other hand, what a completely fascinating study! This is an interesting insight that might actually lead to some good follow up research. Time will tell.

Monday, May 24, 2010

Struck Off: Dr. Wakefield

Dr. Andrew Wakefield has been struck off the medical register in the United Kingdom. He has been in effect, de-licensed. Dr. Wakefield drew a connection between the Measles Mumps and Rubella vaccine and autism, which evolved into a number of movements. He didn’t begin these movements (they predated him, possibly significantly in some circles), but he gave them credibility.

Way back in 2005,
I wrote about some of the problems these movements caused. And also why the premise was flawed. What was true then is still true today, but even more so. It is easy to search and find an extensive list of Dr. Wakefield's sins, which we didn't know about in 2005.

Saturday, May 22, 2010

New GFCF Study

A new GF/CF study will be presented at IMFAR. Hyman et al (2010) took a challenge based approach, which is different from what has been seen so far. The authors enrolled 22 pre-school aged children and placed them all on a GF/CF diet. The children were given a snack once a week that either contained gluten/casein or placebo. Snacks that contained gluten and/or casein were designed to be indistinguishable from the snacks that did not. This was described by the authors as an “exercise in innovative cooking.”

Strengths:

Innovative design
Nice use of a challenge based methodology
Solid, double blind methodology
Smart controls over history and maturation threats

Weaknesses:
22 participants is a respectable number, but it still could have been higher.
Can’t answer for the diet’s efficacy for children with actual bowel conditions (Celiac etc)

Conclusions:
The autism community has been waiting a long time for a study like this. The best we have seen up till now has been the Elder (2006) study. The methodology is simply rock solid.

Predictions:

I do not predict that this study will have any effect on the advocates of the GF/CF diet. For some reason the GF/CF advocates have been more polite than some of their colleagues. They have typically responded to negative GF/CF studies by trying to find flaws in the study methodology, rather than silly accusations about “shills”.
They will do the same here, I think. My guess is that they will target the number of participants (which is silly in this case). They will also target the time-span (18 weeks) the children were on the GF/CF study in total and on the diet before the first gluten/casein snack was given (4 weeks). Such criticism will be irrelevant however, as there are no standards in this regard. I expect plenty of goal posts to be shifted. I am convinced at this point that being an academic GF/CF advocate means never having to pick an actual study length.

Tuesday, May 18, 2010

Medical Hypotheses

Medical Hypotheses is a non-peer reviewed journal founded by the late David Horrobin. The way Dr. Horrobin is described varies greatly. I have heard him described as a brilliant, if somewhat eccentric scientist. A serious researcher with over 900 peer reviewed articles. An entrepreneur who marketed his products without having demonstrated their safety. And according to an obituary published in the British Medical Journal “he may prove to be the greatest snake oil salesman of his age”.

Dr. Horrobin founded Medical Hypotheses in part to serve a unique niche. It was to be a place where hypotheses and ideas could be published in the absence of a sometimes stifling peer review process. It was a sort of book of the month club, with articles picked by the editor because they were “interesting and important”. And to be fair, some undoubtedly produced good in the world.

However, this journal also left the door open for quacks. It gave the appearance of “science” without its discipline or rigor. And while maybe something like Medical Hypotheses was necessary in 1975 to serve as the coffee house for novel scientific ideas, it is obsolete in 2010. That role is better served by the internet; which is more accessible, has a bigger audience, is even less censored, and lacks stifling page limits. The only thing that an internet blog lacks is the assumed stamp of quality science.

Long story short, Elsevier, the publisher of Medical Hypotheses has had enough. They fired the current editor and are about implement peer review. In my view this came a dollar short and day late, but I am genuinely glad. It strips away an undeserved authenticity for those using Medical Hypotheses to promote autism quackery.

Full story here

Tuesday, May 11, 2010

About Interverbal

About Interverbal, both the person and the blog.

I am employed in the field of Special Education. I am current or past member of several behavior analytic, gifted/talented, and special educational professional organizations. I formally declare that I am financially vested in none of these societies.

All visitors to this blog are welcome to comment in a manner they see fit. Vehement disagreement is permissible; however comments must be on topic, and must involve actual argumentation. No drive by character assassination or trolling please. Also, no services, events, or research recruitments may be advertised on this blog…period.

Violating posts will be removed.