Dear Paul,
I agree that complaining that CAM can't be subjected to RCT is erroneous.
According to the Low Back Task Force from the Bone and Joint Decade there
are more RCTs on needle acupuncture (19 RCTs) and spinal
manipulation/mobilization (13 RCTs) then there are for NSAIDs (5 RCTs),
muscle relaxants (5 RCTs) or analgesics (5 RCTs). (1)
There are modifications that need to be made for some CAM therapies when
considering blinding. Obviously, one cannot blind the doctor performing
needle acupuncture or spinal manipulation as to whether they are providing
the active or sham treatment. However, it is pretty much standard to
instead blind the doctor who is measuring the dependent variable.
Another possibility which has been tested in a pilot study which is in press
is the use of short acting anesthesia to prevent the subject from knowing if
they were treated at all.
Finally, Eisenberg and colleagues (2) conducted a study where they let
subjects choose their CAM treatment rather than blinding them. The
rationale is that blinding is supposed to eliminate subject bias but when
providing a treatment that the subject knows they are getting they can have
a negative bias if randomized to something they don't want. E.g.
randomizing a patient who wants massage to acupuncture introduces a negative
bias. In this study one can assume that all subjects getting the treatment
of their choice have positive bias towards their treatment which should be
common to all.
Stephen
1. Haldeman S, Dagenais S. What have we learned about the
evidence-informed management of chronic low back pain? Spine J. 2008
Jan-Feb;8(1):266-77.
2. Eisenberg DM, Post DE, Davis RB, Connelly MT, Legedza AT, Hrbek AL,
et al. Addition of choice of complementary therapies to usual care for acute
low back pain: a randomized controlled trial. Spine. 2007 Jan
15;32(2):151-8.
Stephen M. Perle, D.C., M.S.
Associate Editor, Chiropractic and Osteopathy
Professor of Clinical Sciences
Adjunct Professor of Mechanical Engineering
University of Bridgeport, Bridgeport, CT 06604 USA
www.bridgeport.edu/~perle
Ethics Articles www.chiroweb.com/columnist/perle
Speaker's Bureau www.ncmic.com/6026/speakers.htm
Chiropractic and Osteopathy www.chiroandosteo.com
________________________________________
Real knowledge is to know the extent of one's ignorance.
- Confucius
> -----Original Message-----
> From: Evidence based health (EBH) [mailto:EVIDENCE-BASED-
> [log in to unmask]] On Behalf Of Paul Glasziou
> Sent: Monday, January 05, 2009 6:39 AM
> To: [log in to unmask]
> Subject: Re: Fw: Special Issue:Evidence in Evidence-Based Medicine Fw:
> Social Epistemology - informaworld
>
> Dear Frances,
> Yes - the articles seem to include a hoard of straw men. And doesn't
> seem well informed by evidence. For example, the claim that CAM can't be
> tested by RCTs because "Randomisation and
> standardisation are foreign, and often incommensurate, concepts in CAM"
> has been neatly tested and refuted by Bensoussan[1], who did a 3-arm
> randomised trial of (i) standard chinese herbs (ii) *individualised*
> herbs (tailored to that persons unique constellation) and (iii) placebo
> for irritable bowel syndrome. Both chinese herb groups did better but
> individualisation did no better than standardised. This is *not* cited
> by any author (thanks Alejandro for the pdf that allowed be to search
> that).
> I also note there seemed to be no one from the clinical coalface in the
> group of authors, which may help explain their apparent disconnection
> from the realities of clinical practice and why we need EBM. But they
> would have done well to first read Sharon Straus's review of the
> criticisms of EBM[2], which might have saved them some time inventing
> straw men.
> Happy New Year,
> Paul Glasziou
> 1. Bensoussan A, Talley NJ, Hing M, Menzies R, Guo A, Ngu M. Treatment
> of irritable bowel syndrome with Chinese herbal medicine: a randomized
> controlled trial. JAMA. 1998 Nov 11;280(18):1585-9.
> 2. Straus SE, McAlister FA. Evidence-based medicine: a commentary on
> common criticisms. CMAJ. 2000 Oct 3;163(7):837-41.
>
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