Another large international
trial is published, and another standard practice based on little more than our
bias towards doing something rather than doing nothing is reversed.
Saturday, 18 June 2016
Saturday, 12 March 2016
Book review, of my book: Surgery, the ultimate placebo.
This will be a test of
how unbiased I am. Writing a review of my own book (regardless of any bias) seems
like shameless self-promotion, but what the hell, it's better than just saying "Hey, I wrote a book".
Saturday, 13 February 2016
Knee arthroscopy for "mechanical symptoms"
I have previously written about the (non)
role of arthroscopy for osteoarthritis or degenerative meniscus tears in the
knee (here,
here
and here).
Surgeons have continued to operate, based on a belief that (now) centres on the
presence of mechanical symptoms. An analysis of the recent sham surgery trial
of arthroscopic partial meniscectomy (APM), which showed APM to be no better
than sham for patients with meniscus tears without arthritis, has shown that
this procedure is no better than sham surgery for patients with mechanical
symptoms.
Monday, 2 November 2015
Laparoscopy for bowel adhesions
Laparoscopy is keyhole surgery of the abdomen in which a
camera and instruments are inserted through holes in the skin, into the abdomen
to see the structures within (diagnostic
laparoscopy) and to correct pathology where possible (therapeutic laparoscopy). In patients that have had previous
pathology or surgery to the abdomen, adhesions can develop whereby loops of bowel
can get caught up in scar tissue. If this causes an obstruction of the bowel,
it can be very serious, but often people just have abdominal pain that coexists with adhesions.
Sunday, 4 October 2015
Prophylactic mastectomy
Prophylactic mastectomy reduces the risk of getting breast
cancer (here),
but does it reduce your overall risk of dying? And what are the other risks?
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.
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.
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