Wednesday, 8 August 2007

A cracking example of a pseudojournal

It turns out there is a journal called Homeopathy. It looks very like a proper journal. It is peer reviewed, it is indexed in the Web of Science, and it is published by Elsevier. If you look at the page layout, it looks not unlike the Journal of Structural Geology; it has that journal format to it. But this is definitely not a scientific journal. It is a pseudo-journal that publishes pseudo-science, and its reviewers are pseudo-scientists.

The journal has recently published a special issue on the memory of water (as so often, Ben Goldacre's site is responsible for the heads up). This is an important topic for homeopaths, because it provides a way in which homeopathy might work. The water that contains the homeopathic 'remedy' is diluted such that none of the 'remedy' can possibly remain, so homeopaths fall back on the notion that the water somehow structurally 'remembers' the remedy. Some proper scientific work that got published in Nature suggested that the actual length of time water can structurally remember anything is on the order of 50 femtoseconds, so this is probably a non-starter. Those brave homeopaths have taken on the blinkered scientific establishment and had a go, nonetheless.

Oh, it's a shambles.

In it, Martin F Chaplin has a paper entitled 'The Memory of Water: an overview'. But this paper contains no evidence of water having a memory at all. Chaplin's examples of 'evidence for water memory' have nothing to do with water 'remembering' a solute that has been diluted out of existence. For example, 'human taste is quite capable of telling the difference between two glasses of water, processed in different ways (eg one fresh and one undrunk for several days.)' Yes, that’s because they will contain different amounts of dissolved gases from the atmosphere. What would be really interesting is if you could taste the difference, say, between two 30C dilutions of different solutes prepared under identical conditions. Chaplin also mentions a 'memory effect' related to clathrate formation. Again, this isn't relevant to whether a solute that is diluted out of existence has any effect on the water structure. And again, there is a mention of 'slow equilibration' of solutions. But this isn’t relevant to cases where no solute is present.

Then there are the 'experimental papers'. The paper by Elia et al. is so poorly organised and written that it isn't clear what they did. However, they do say 'It is important to emphasise that, from the studies so far conducted, we cannot derive reproducible information concerning the influence of the different degrees of homeopathic dilution or the nature of the active principle (solute) on the measured physicochemical parameters'. What this seems to say is that none of the results they present are reproducible, so they can't really be considered to represent results in any scientifically meaningful sense.

The paper by Rao et al. seems to have some serious problems with the reported spectroscopy, which is dealt with here. My personal favourite section is where the paper suggests that 'it can be argued' that the succusion process (shaking of the homeopathic remedy between dilution steps) could produce pressures of up to 10 kbar. Perhaps this point can be argued, but the authors don't make any attempt to argue it. They also state that grinding in a mortar and pestle can produce pressures up to 20 kbar, for which they give a reference to a paper by Dachille and Roy, which is number 22 in their reference list. In fact, their reference no. 22 is to a Bates et al. paper in Science, which looks at high-pressure forms of Germanium. The paper contains no mention of mortar and pestle at all. This sort of bad referencing would be picked up by any thorough review. But anyway, 10 to 20 kbar? Now, as a geologist, I know that pressure in the crust increases by approximately a third of a kbar per kilometre, depending on rock density. Thus 10 kbar is equivalent to a depth of 30 km, and 20 kbar is equivalent to a depth of 60 km. So if I shake up a homeopathic solution, I can get a pressure equivalent to 30 km of rock, and if I grind up some shale in a mortar and pestle, I end up with a blueschist facies metamorphic rock. 10 kbar is on the order of 10,000 atmospheres. This claim seems extremely unlikely, and again is the sort of thing that would be picked up by any half-way competent reviewer.

The paper by Louis Rey seems interesting, but there are issues with reproducibility. None of the graphs contain error bars. Although the author says that his results have been replicated by another lab, he doesn't seem to have tried to replicate them himself. It is just stated that some graphs look different, without any discussion of how statistically significant the differences might be. Again, it's difficult to know whether the paper shows anything at all.

Then there is a paper by Vybiral and Voracek, which looks at some interesting physics of water. However, the authors conclude that the 'autothixotropy' effect that they observe is absent when they use de-ionised water. Thus their effect is related to ions in the water, and not any 'water memory' effect which would be due to ions that were previously in the water, but are no longer there.

After that there are some 'theoretical' papers, which contain no new evidence, and some bizarre excursions into the world of quantum mechanics, which luckily are dealt with here.

In short, the entire issue seems to contain no good evidence in support of its title 'The Memory of Water is a Reality'. And yet this will now be cited by homeopaths for evermore as peer-reviewed scientific evidence for how homeopathy might work. Of course, all the evidence suggests that homeopathy doesn't work at all, so there's no need to explain how it works in the first place. What a waste of time.

To give Homeopathy its due though, it did publish a paper by Jose Teixeira, entitled 'Can water possibly have a memory? A sceptical view'. The paper concludes that 'any interpretation calling for ‘memory’ effects in pure water must be totally excluded', on the grounds that 'the longest life of any structure observed in liquid water is of the order of 1 ps'. So much time and effort could have been saved.

Edit: There's a far better overview than the above somewhat amateur attempt at Philip Ball's blog, which is why he writes for Nature and I don't. I can't link directly to the post itself, but look for the August 03 2007 entry entitled 'A bad memory'. There are also comments from Martin F Chaplin there.


Revisor said...

This article demonstrates poor arguments. And abundant ad-hominem fallacies. Is a prejuicious article, based in only opinion of autor.
The Journal of Homeopathy is a Journal, not "pseudo Journal". This blog is simple pseudo science.

Paul Wilson said...

So you say, but you commit the cardinal error of not bothering to actually put any arguments forward yourself...