Wednesday 29 July 2009

Solidarity

My apologies for the long delay in posting and the dearth of new material on this post. All I can do is assure you that I am still alive, but merely very busy with my PhD and a publication... Today sciencey and not so sciencey blogs across the web are re-publishing an article by Simon Singh about the many dubious claims of chiropractors and the British Chiropractic Association in particular. I have made reference to some of the poorly-supported claims of the BCA in a previous blog entry. I've also discussed how scientists go about refuting dubious claims. Science is an adversarial system in which our claims and the evidence upon which they are based are subjected to close scrutiny and, if they appear weak, are attacked. We debate, we refute with contradictory evidence, we put forward alternative explanations for the observable facts. We do not litigate, because litigation silences a scientific debate and transfers it into a courtroom so that some lawyers can have a financially ruinous legal debate.

But the BCA sees things differently. When last year Simon Singh pointed out how weak the evidence in support of chiropractic really is, the BCA reacted not with scientific evidence, nor logical argument. They sued him. That action is now ongoing and has been commented on by Bad Science. For science to progress, debate must be free and open and won on the basis of evidence, not legal funds. This is especially important when it comes to health, because when debate about medical science is stifled, bad practices persist and the outcome is suffering and death. Whether chiropractic is effective and safe will never be determined by a judge. If any of this bothers you sufficiently, the British organisation Sense About Science have a petition you can sign.

The original Singh article (modified to avoid the BCA's litigation bat) is reproduced below, as it has been reproduced by Sharon at The Voyage, Pharyngula and many other blogs. Feel free to refute it with scientific evidence!

Beware the spinal trap

Some practitioners claim it is a cure-all, but the research suggests chiropractic therapy has mixed results - and can even be lethal, says Simon Singh.

You might be surprised to know that the founder of chiropractic therapy, Daniel David Palmer, wrote that "99% of all diseases are caused by displaced vertebrae". In the 1860s, Palmer began to develop his theory that the spine was involved in almost every illness because the spinal cord connects the brain to the rest of the body. Therefore any misalignment could cause a problem in distant parts of the body.

In fact, Palmer's first chiropractic intervention supposedly cured a man who had been profoundly deaf for 17 years. His second treatment was equally strange, because he claimed that he treated a patient with heart trouble by correcting a displaced vertebra.

You might think that modern chiropractors restrict themselves to treating back problems, but in fact some still possess quite wacky ideas. The fundamentalists argue that they can cure anything, including helping treat children with colic, sleeping and feeding problems, frequent ear infections, asthma and prolonged crying - even though there is not a jot of evidence.

I can confidently label these assertions as utter nonsense because I have co-authored a book about alternative medicine with the world's first professor of complementary medicine, Edzard Ernst. He learned chiropractic techniques himself and used them as a doctor. This is when he began to see the need for some critical evaluation. Among other projects, he examined the evidence from 70 trials exploring the benefits of chiropractic therapy in conditions unrelated to the back. He found no evidence to suggest that chiropractors could treat any such conditions.

But what about chiropractic in the context of treating back problems? Manipulating the spine can cure some problems, but results are mixed. To be fair, conventional approaches, such as physiotherapy, also struggle to treat back problems with any consistency. Nevertheless, conventional therapy is still preferable because of the serious dangers associated with chiropractic.

In 2001, a systematic review of five studies revealed that roughly half of all chiropractic patients experience temporary adverse effects, such as pain, numbness, stiffness, dizziness and headaches. These are relatively minor effects, but the frequency is very high, and this has to be weighed against the limited benefit offered by chiropractors.

More worryingly, the hallmark technique of the chiropractor, known as high-velocity, low-amplitude thrust, carries much more significant risks. This involves pushing joints beyond their natural range of motion by applying a short, sharp force. Although this is a safe procedure for most patients, others can suffer dislocations and fractures.

Worse still, manipulation of the neck can damage the vertebral arteries, which supply blood to the brain. So-called vertebral dissection can ultimately cut off the blood supply, which in turn can lead to a stroke and even death. Because there is usually a delay between the vertebral dissection and the blockage of blood to the brain, the link between chiropractic and strokes went unnoticed for many years. Recently, however, it has been possible to identify cases where spinal manipulation has certainly been the cause of vertebral dissection.

Laurie Mathiason was a 20-year-old Canadian waitress who visited a chiropractor 21 times between 1997 and 1998 to relieve her low-back pain. On her penultimate visit she complained of stiffness in her neck. That evening she began dropping plates at the restaurant, so she returned to the chiropractor. As the chiropractor manipulated her neck, Mathiason began to cry, her eyes started to roll, she foamed at the mouth and her body began to convulse. She was rushed to hospital, slipped into a coma and died three days later. At the inquest, the coroner declared: "Laurie died of a ruptured vertebral artery, which occurred in association with a chiropractic manipulation of the neck."

This case is not unique. In Canada alone there have been several other women who have died after receiving chiropractic therapy, and Edzard Ernst has identified about 700 cases of serious complications among the medical literature. This should be a major concern for health officials, particularly as under-reporting will mean that the actual number of cases is much higher.

If spinal manipulation were a drug with such serious adverse effects and so little demonstrable benefit, then it would almost certainly have been taken off the market.

Tuesday 12 May 2009

Casey Luskin is The Wedge

There's a multimedia element to my post this time around. Well, an annotated YouTube video. Trust me, the stupid isn't nearly as compelling until you watch it.

Discovery Institute front-man Casey Luskin appeared on Fox News' rather conservative "Fox and Friends" show recently to warn us all that we're being hoodwinked by them mainstream science types. Biology textbooks, Luskin claims, neglect to incoproporate any scientific evidence which "contradicts Darwin". Apparently, the teaching of evolution in American schools (and perhaps elsewhere) is plagued with inaccuracies. This quite modest plague apparently consists of two items which, if you can believe it of a God-fearing institution, are total bullshit. Isn't it strange how the people raising this most important issue also happen to be peddling Intelligent Design, a crudely-disguised version of Creationism. The presenter correctly identifies that the teaching of evolution is a "white hot" issue. I guess the failure of the show to bring on someone from say, the other side of the debate, to speak on the show may have something to do with that "and Friends" bit of the show title.

First up in the non-torrent of non-issues is the apparent inclusion of the debunked "Haeckel's Embryos" illustrations in biology texts, which I have to admit I have never seen presented as factual. Of course, what Luskin does not mention is that the point that Haeckel's admittedly fabricated drawings of vertebrate embryos compared side-by-side has in fact been fully validated by genuine embryology work. This work has shown that we can find common combinations of morphological traits between the embryos of the vertebrate species. We gain an insight that we don't always get from comparing adult organisms. It is this modern and well researched take on Haeckel's work is what we typically find in biology texts. And it is that science which actually upsets Luskin and company who, it is repeated so many times as to be suspicious, do not want to teach your kids creationism. For definite. Okay?

Second, the ghost of a recent New Scientist article (which screamed Darwin Was Wrong from the front cover before going on to essentially admit that he... wasn't wrong) is summoned to frighten us. The article discussed the phenomenon of horizontal gene transfer (HGT), whereby genetic material can pass from one species to another without descent. HGT makes a mess out of the lineage of the bacteria because they make such transfers quite frequently. However, Casey Luskin would like us to believe that this has proven wrong the concept of the tree of life entirely. But HGT is quite remarkably rare amongst species bigger than the single-celled organisms that live in in the humid forests of Luskin's substantial eyebrows. The awkward truth that Luskin and other ID proponents need to explain is why when we arrange bigger, multicellular species by the combinations of common traits they posses, we get a tree shape. That's just how their traits are distributed, the tree is not a human fabrication and it is certainly not under threat. It's taught as a part of evolution because when it comes to the animals and plants we see around us, it's very much real and relevant.

Luskin's entirely unchallenged arguments are aired here, with some added annotations from yours truly.