Sunday, 23 August 2015

Sham physical therapy

Paradoxically, it is easier to perform a sham trial in surgery, the most invasive physical act, than in physiotherapy because the patient is asleep when it is delivered. Physical therapy involves physical acts that are hard to imitate as placebo treatment, but the influence of the patient-therapist interaction makes it important to tease out any placebo effect. Researchers have, however, performed sham trials in physiotherapy.

Saturday, 15 August 2015

Fixing a hole

Migraine is common, affecting millions of people worldwide. A patent foramen ovale (PFO – a ‘hole in the heart’ that lets blood cross from the right heart to the left) is common as well, present in about 30% of people. When cardiologists started surgically closing PFOs, they noticed that many patients with migraine got better. As with the discovery of any association in medicine, theories of a causal link soon followed, and doctors started treating migraine by closing the hole in the heart; before properly testing it, of course.

Tuesday, 19 May 2015

Placebo trials of surgery

In a recent systematic review of placebo trials of surgery (here) it was found that in half of the 53 trials found, surgery was not better than placebo treatment. And in the ones where it was better, the difference wasn’t great. This may not be big news to my readers, but this review was important because it highlighted many of the problems with surgery, namely that:
1) placebo studies are needed to determine the true effectiveness of surgical procedures, but …
2) surgery and associated devices are regulated less strictly than drugs, consequently …
3) surgery is often not subjected to placebo / sham studies, even though …
4) such studies are ethical and practical.

Sunday, 17 May 2015

My right foot: predicament versus illness

My right foot hurts. It hurts in the middle, underneath, but not all the time, and only when I walk or take any weight on it, especially when I get up in the morning, when it becomes difficult to walk. It has been hurting on and off since I did an 80km trek three months ago. It could be a stress fracture, or some kind of fasciitis, soft tissue tear, fatigue, injury or degeneration, but I don't really care, because I am not going to have any tests or see any health care practitioners to get their version of a diagnosis. I'm just going to leave it alone. I am going to be a person with a predicament that I can cope with, and not a patient with an illness.

Tuesday, 28 April 2015

Do shoulder fractures need surgery?

Fractures that occur at the upper end of the humerus near the shoulder (called humeral neck fractures) are common. They are often treated with surgery despite a lack of supporting evidence for this, particularly in older, osteoporotic patients. Now, thanks to a recent study from the UK, it is possible that most of these fractures don’t need surgery, even in young patients. This is big news, but will this research jump the gap from research into practice and influence the decision making of the end users – the patient and their surgeon?

Monday, 8 December 2014

Predatory publishing: when scientific quality gets in the way of a good business model

Science progresses because it is open to scrutiny. For findings to be accepted, they must pass peer-review and must be presented to other scientists for them to question, refute, or confirm. Publication in a scientific journal (and presentation at conferences) is key to this process. However, the number of journals and conferences have increased massively over the last 10 -20 years, and many of them are not the real thing – so called ‘predatory’ publishing and predatory conferences have sprung up everywhere. The problem with this is that there is no clear line between what is real and what is fake.

Sunday, 26 October 2014

Lessons from history #13: Hormone replacement therapy

Hormone replacement therapy (HRT) for post-menopausal women was thought to decrease the chance of cardiovascular problems like heart attack and stroke. This ‘made sense’ because the risk of cardiovascular disease in women rose sharply after menopause, indicating that female hormones had a protective effect. Many large observational studies supported this belief, and HRT was widely prescribed in the 1980s and 1990s. Later evidence from large, placebo controlled, randomised trials failed to show any cardiovascular benefit. Again, observational evidence was shown to overestimate the effectiveness of a common medical treatment and again, practice became established before the definitive trials were done.

Sunday, 19 October 2014

Surgery for high blood pressure

The most recent casualty of the sham surgery trial, adding to the list of operations that looked good and had good results until put to the leased biased test, is a procedure called renal denervation (cutting the nerves to the kidney). Years of good results showing that this procedure lowered blood pressure are now met with a blinded sham-controlled trial that showed no significant benefit over placebo.

Thursday, 18 September 2014

The replication problem

One of the fundamental principles of science is that the results of any experiment should be reproducible. Reproducibility is essential because it means that the results can be relied upon, as they are more likely to be true. Unfortunately, there is little fame in replicating someone else’s study; it is also hard to get such studies funded (because they are not ‘novel’). Consequently, many studies are not repeated and many findings stand alone without verification from separate, independent researchers. This is a problem because often when studies are replicated, they fail to reproduce the original findings.

Wednesday, 10 September 2014

Astroturfing

Patients should have a voice in medical policy and treatment. ‘Grass-roots’ groups of patients are more likely to have that voice heard and to effect change if they are organised and well funded. Patient advocacy groups can therefore be more effective if they accept industry (pharma) funding. However, such groups can also serve the interests of the industry doing the funding. It is even better for the industry, however, if they organise the grass-roots patient advocacy group from the start; so-called ‘astroturfing’.

Sunday, 17 August 2014

Lessons from history #12: Lobotomy

In the 1940s and 50s (tapering into the 70s and 80s) tens of thousands of prefrontal lobotomies (severing the front part of the brain) were performed in Europe and North America for many types of mental conditions. It was done because doctors at that time believed that it worked, and they didn’t have many effective alternatives. However, it didn’t work, it made people worse and it even killed a few, despite a Nobel prize being awarded to one of the developers of the procedure.

Monday, 11 August 2014

Lessons from history #11: Extra- to Intra-cranial Bypass Surgery

This story is about a procedure that made sense and had supporting evidence, became common practice, but was later discontinued because a high quality study showed it to be ineffective. The story of extra-cranial intra-cranial bypass surgery ticks all the boxes: overestimation of benefit, seduction by the theory, unrecognised bias in studies, and just plain ineffectiveness despite our best effort and beliefs.

Friday, 27 June 2014

Lessons from history #10: How magnesium lost its mojo

Wouldn’t it be great if there was a cheap, non-proprietary, readily available treatment for patients with heart attacks (acute myocardial infarction - AMI)? That’s what doctors wanted to believe, so when they saw the early results of magnesium therapy, they did exactly that. Magnesium therapy for AMI has been labelled a “lesson in medical humility”, but I see it as another example of the pervasive bias amongst researchers, doctors and the public that leads them to overestimate the effectiveness of medical therapies. Put simply, it was another case of ‘believing is seeing’.

Sunday, 22 June 2014

Animal research: just another WOFTAM?

The idea is that experiments are first performed in the lab, are then performed in animals, and these experiments inform the eventual human studies. As a (seemingly) necessary step in this chain, animal experiments are (rightly or wrongly) tolerated based on their eventual benefit to humans. Animal studies however, are not good predictors of human trials, often do not inform human trials, and are methodologically inferior to human trials, so much so, that the results from animal studies are unreliable and biased. In other words, animal studies are often of no benefit to humans. Arguably, they do not benefit humans at all, let alone enough to justify their use. We either need to fix the problem or get out of the animal research game.

Sunday, 27 April 2014

Surgery for shoulder impingement

When you raise your arm, the top of your humerus, where the rotator cuff tendons attach, “impinge” against your acromion. When this hurts, it is called impingement syndrome. “Decompressing” the joint by taking some bone off the acromion (an "acromioplasty”) makes sense, and seems to work well. The operation has been around for a long time, and there have been many studies looking at different ways of doing this operation, but very few studies looking at whether or not it works better than not operating. Interestingly, all of the studies that have been done conclude that this operation adds nothing.

Friday, 25 April 2014

Book/Web review: Testing Treatments

Title: Testing Treatments 2nd Ed, 2011
Authors: Imogen Evans, Hazel Thornton, Iain Chalmers, Paul Glasziou
Publisher: Pinter and Martin, London
Website: testingtreatments.org

Testing Treatments is a book, and Testing Treatments Interactive (http://www.testingtreatments.org/) is a website that contains the book, with live links and added information. It is a valuable reference tool for the layperson and also useful for health practitioners who are not well versed in evidence-based medicine. The book tells you why it is important to test treatments, how this type of testing should be done, and how to make research better and more useful to future patients.

Sunday, 16 March 2014

Manufacturing significance

What if I could produce an experiment that concluded that listening to an old song could make you younger? Not feel younger, but be younger. Impossible, of course, but the story of how this can be achieved is a great example of how easy it is to produce statistically significant findings in science. All you need is enough 'wriggle room' in the data and a pre-conceived notion of what the results will be. Like ghosts in The Sixth Sense, scientists often only see what they want to see.

Monday, 10 March 2014

When the antivenoms don’t work, you gotta start asking questions

As a junior doctor in Australia, the country with the deadliest snakes and spiders in the world, you quickly learn where the antivenoms are kept. Now it appears that the deadliness of these critters is less than we thought, and the benefits of the anti-venoms are under question, or have been proven to be ineffective.

Sunday, 23 February 2014

The Hope Peddlers

When treatment choices are limited or when true effectiveness is not clear, patients want hope: they want to have a chance to get better. Doctors hold this valuable commodity, and dispense it on demand, for a fee, after which they claim any perceived improvement as being due to their efforts. Even when a treatment is not proven to be effective, or when it is proven to be no better than placebo, doctors too easily fall into the role of hope-peddler, without considering the hidden costs or unintended consequences.

Friday, 24 January 2014

Does removing breast cancer affect survival?

Allow me to make an assertion: breast cancer survival is not influenced by surgical excision of the primary tumour. This goes against the prevailing wisdom that cancer is cured by removing it, but that kind of thinking is simplistic and at odds with much of the evidence. Lets walk through that evidence.