I had commented on that well-publicized recent study of acupuncture 
for migraines:

> To evaluate placebo, we need a no-treatment control group for
> comparison, something that many placebo controlled studies don't 
 > have. Let us know when you get your hands on the study, David.

Now that David has come through with the study, I can answer my own 
question.  There was none.

The study found that fake acupuncture, real acupuncture, and rather 
modest (as David pointed out)  "standard therapy" were not 
statistically different in terms of their effect on migraine attacks. 

So did the authors honestly conclude that they had failed to show 
that acupuncture works? Hell, no. They instead concluded in their 
paper that "the most important result is that all three treatments 
were effective", which was trumpeted in the press as "Acupuncture 
works for migraine".

Their only evidence that it worked was that the number of migraine 
days during a four week period before randomization (approx 1 per 
week)  was about 50% greater than at the end of treatment, 22-26 
weeks later. This carries the implicit assumption that the frequency 
of migraines remains stable over the next six months. Maybe, maybe 
not.

In the absence of their experimental group showing superiority over 
their placebo group, what they need to declare that _all_ groups were 
effective is a no-treatment group which did worse. Having none, their 
positive spin on the experiment is merely hot air. It's just as 
plausible that rather than all of the treatments working, none of 
them did. 

Stephen

Diener, H. and a whole bunch of others. (2006). Efficacy of 
acupuncture for the prophylaxis of migraine, yada, yada.Tthe Lancet 
Neurology, on-line March 2.

-----------------------------------------------------------------
Stephen L. Black, Ph.D.          
Department of Psychology     
Bishop's University                e-mail:  [EMAIL PROTECTED]
Lennoxville, QC J1M 1Z7
Canada

Dept web page at http://www.ubishops.ca/ccc/div/soc/psy
TIPS discussion list for psychology teachers at
http://faculty.frostburg.edu/psyc/southerly/tips/index.htm
----------------------------------------------------------------------


---
You are currently subscribed to tips as: [email protected]
To unsubscribe send a blank email to [EMAIL PROTECTED]

Reply via email to