Is Dr Tom Dolphin regretting his statement that “Homeopathy is witchcraft“?
I do hope not. Whilst it is perhaps an affront to witches and wiccans to be lumped in with homeopathy, they do not (yet) seem to have been particularly vocal on the matter. This statement at the BMA junior doctors conference has brought another touch of publicity to the ten23 campaign (follow #ten23 on twitter), and put the continued NHS funding of homeopathy back in the spotlight.
This, in turn, has resulted in another round of interviews on chat shows such as the Jeremy Vine show on BBC radio 2 on 17th May 2010, (Listen from 1hr 08 min – only available in the UK) where an NHS Homeopath (Dr Bob Leckridge), 2 pro-homeopathy and 1 anti-homeopathy callers joined with Radio 2 resident GP Dr Sarah Jarvis to run a few more rounds of the “homeopathy is witchcraft” and perhaps the more pertinent “should homeopathy be funded on the NHS” debates. It also seems that Dr Leckridge had prior knowledge of the case outlined with the first caller – which smacks of a planted, pre-arranged caller – which is a little duplicitous at best – *if* this was done on purpose by the BBC, this is evidence of clear bias in their reporting/coverage of this matter. E-mails shall be sent.
It should be pointed out that as a properly qualified MD, Leckridge is the best sort of homeopath. It would interesting to see whether or not he agrees with some of the grander claims that some homeopaths make about being able to cure cancer and malaria.
Anyway, I’ve listened to quite of a few these now, and you get to spot the same old patterns repeating over-and-over again. In addition to this, Dr Leckridge made some rather sweeping statements on the radio that I would like to address.
The anecdotal evidence submitted by callers is clearly irrelevant, as it is uncontrolled, and “the plural of anecdote is not data”.
1) Some people get better after seeing a homeopath.
This is a classic post hoc ergo propter hoc or “false cause“ fallacy – just because someone gets better, doesn’t necessarily mean that it was the seeing of a homeopath or taking of a sugar pill that made them better. This is why we have randomised controlled trials using statistically significant numbers of patients. It is also why we conduct lots and lots (and lots) of scientific experiments to try and define and determine a mechanism of action for a genuine, conventional pharmaceutical remedy. We have only had the tools to ‘discover’ this level of proof en masse for the past 20-30 years or so. And yes, there are many genuine, conventional pharmaceutical remedies for which we have not a determined molecular mechanism… which allows us to neatly segue into fallacy #2.
2) We don’t know how X works, therefore homeopathy does/can work too.
An “argument from ignorance” fallacy.
In the above Jermey Vine show, Homeopath Dr Leckridge stated that “we don’t know how antidepressants work” – and to a certain point, he’s correct. I’m a molecular mechanisms kind of guy – let’s take a look at Prozac, aka Fluoxetine. A quick search of PUBMED reveals that only 7451 papers have the word “Fluoxetine” in their title or abstract. Only 28 Cochrane library reviews contain the word “Fluoxetine” in their title/abstract. Only.
We know that Fluoxetine is an Selective Serotonin Reuptake Inhibitor, in that it selectively inhibits serotonin reuptake (duh) and that Fluoxetine leads to the phosphorylation (activation) of ERK1/2 MAP kinases, most probably by interacting with the 5-HT2b receptor. We don’t know precisely how this activation of ERK1/2 leads to inhibition of serotonin reuptake. We do, however have good RCT evidence for the efficacy of Fluoxetine for depression, Obsessive compulsive disorder, bulimia nervosa, panic disorder and more.
But because we haven’t yet joined up the dots from ERK1/2 activation to inhibition of serotonin reuptake, the mechanistically implausible affront to rational thinking that is homeopathy works, right? Wrong. (I should mention here that we do not know the molecular mechanism for any homeopathic remedies, mostly because they do not have molecules in them.)
3) My dog/horse/cow/alpaca/kitten/parakeet/child got better after I gave them homeopathy? How can it be the placebo effect if it worked on them?
This is simply not the case. In an everyday situation, the owner of the animal / parent of the child knows what treatment the animal / child is getting, and their interaction with and perception of the disease state the animal / child is influenced by that.
Even in RCT situations, children and animals have shown to be susceptible to the placebo effect.
Placebo efficacy in childhood and adolescence migraine: an analysis of double-blind and placebo-controlled studies.
“The placebo effect is well documented in animal trials [12,3,24], and explained by Pavlovian conditioning”
from here (and refs therein) and an interesting piece in the Science based medicine blog (and refs therein)
4) NHS doctors just want to pump us full of antibiotics for respiratory tract infections. Therefore homeopathy works?
This point was neatly refuted by Dr Jarvis on the show, and even if it were not, it does not mean that homeopathy works or that homeopathy should be funded on the NHS. As such it is a complete non sequitur.
It is worthy of note that the excellent NHS choices website contains information on the treatment of RTIs:
The outlook for respiratory tract infections is generally good. Most infections are self-limiting, which means that they will pass without the need for treatment.
However, extra care and additional treatment may be required for people who are more vulnerable to the effects of infection.
5) There is in-vitro evidence for the effect of ultra-dilute homeopathic remedies.
Quite simply, NO, there isn’t. Every paper I have seen that seeks to show an effect of an ultra-dilute homeopathic remedy in cell culture systems has some sort of critical flaw, whether it be the basophil excitation assay that Maddox et al demonstrated to be nothing more than wishful thinking, or the more recent cell culture papers by Sunila et al or Frenkel et al, they have all been shown to be poorly designed experiments, which more often than not, report the effect of ethanol or silicates in cell culture.
(It is worthy of note that apparently an unwilling author on the Frenkel et al paper has now come forwards and raised further problems with that paper.)
As happens time and time again, when thrust into the glare of publicity and public scrutiny, homeopathy fails to convince and resorts to the same old misdirection and misinformation.