Book review: Overdiagnosed

Title: Overdiagnosed. Making people sick in the pursuit of health (2011)

Author: H. Gilbert Welch (with Lisa Schwartz and Steven Woloshin)

Publisher: Beacon Press, Boston

Overdiagnosed is an attempt to change the conventional wisdom - the prevailing paradigm - that early diagnosis is always a good thing and therefore that the best test is the one that finds the most disease. He shows us the downside of our attempt to make sure that nobody misses out on any potential benefit by failing to be diagnosed. He shows us that the dogma of early diagnosis is maintained by overestimated benefits and a general disregard of the harms.

How you die vs If you die

Which is more important: how you die, or if you die? Research in medicine often uses mortality (death) as an important outcome. Death (from any cause, so called ‘all-cause’ mortality) is easy to measure, it is not subject to misclassification, and it is the most important outcome for many conditions and treatments. Many researchers, however, favour ‘disease-specific’ mortality (only counting the deaths from the disease being studied) rather than all-cause mortality. The argument is that this measurement is more sensitive to changes in treatments that specifically target that condition (as there is less ‘noise’ from deaths from other causes). For example, it makes sense to measure deaths from heart disease if you are testing the effect of a treatment for heart disease. However, the use of disease-specific mortality can be misleading, it is arguably less important, and it results in an overestimation of the benefits and underestimation of the harms from many interventions.

Book review: Bad Pharma

Title: Bad Pharma. How drug companies mislead doctors and harm patients (2012)
Author: Ben Goldacre
Publisher: Fourth Estate, London

Ben Goldacre, a UK based doctor, has become a popular medical and science writer. His previous book Bad Science was a big hit, he has popular web and Twitter profiles, and he is a regular public speaker and newspaper contributor. His new book, Bad Pharma, specifically targets the problems with medicines. It does not restrict itself to the pharmaceutical industry (although drug companies are the main target), the book also details problems with government regulators, patient advocate organisations, doctors, medical colleges, governments, journals, universities, academics and even ethics committees. Fortunately, the book also offers solutions.

Limits to medicalization?

The character Syndrome from The Incredibles pictured a world where everybody had super powers: “because when everyone is super, no one will be”. If more than 50% of the population have depression, then what is ‘normal’? What if it was 75% of the population? Are we witnessing a gradual approach to a situation where we will reach the Last Well Person? Is a well person simply a patient who has not been completely worked up?

Stop the medication train, the elderly want to get off

Overmedication (“polypharmacy”) in the elderly is a problem. The debate about the appropriateness of individual medications is one thing, but when you are taking 5 or more different medications multiple times per day, the physical act of simply taking the medication is a problem, let alone the adverse effects and interactions of all these medications. So what happens when you stop taking them? You feel better, that’s what happens.

Lessons from history #4: RSI

Repetitive Strain (or ‘Stress’) Injury (RSI) is a syndrome of arm / hand pain associated with certain activities. It is not a disease. It is not an injury, there is no physical evidence of stress or strain, and it bears little correlation with repetitive use. It is a social construct, influenced more by psychosocial factors than mechanical factors, and has no clear biological basis. Its history shows us how ‘unstable’ such labels are. Yet despite being easy to refute, labels like these persist. They persist because they serve a purpose and appear to fill a gap in our knowledge, and they are more socially acceptable and easy to understand than the truth. They are examples of medicalization.

Opioids: the real opium of the masses

Opioids are strong pain killing drugs that mimic the body’s own chemicals. Examples of prescription opioids include heroin (which metabolises to morphine and was banned after 1925), morphine, oxycodone and hydrocodone. As pain killers for acute pain, opioids work. However, over longer periods they become less effective, have more adverse effects, and can lead to tolerance, dependence, addiction, increased pain, and death. Here are some facts about long-term opioid use.

Treating the numbers, not the patient

What’s your blood count? Blood pressure? Bone density? PSA? If it is abnormal, odds are that you will want it to be normal. In doing so, you are making the same leap of faith that your doctor is making when he commences treatment: that treating the numbers will improve your health. Like much of what we do, treating the numbers is often naïve, and sometimes harmful, no matter how well intentioned. Read these short examples and tell me if you still want your numbers normalised.

Book review: Overtreated

Title: Overtreated: why too much medicine is making us sicker and poorer (2009)

Author: Shannon Brownlee

Publisher: Bloomsbury

There appears to be many books on the topic of overtreatment, overdiagnosis, medicalization, medical error and what’s wrong with modern medicine in general. This book covers all of those topics, but focuses on the simple theme that more medicine does not lead to better health. Instead, it leads to higher costs and worse health.

The Uncertainty Principle: from Heisenberg to Hawthorne

I know that Heisenberg’s Uncertainty Principle refers specifically to physics (in that you cannot simultaneously measure the momentum and position of an electron),¹ and I know that its interpretation has been generalised to the point where some take it to mean that nothing is certain, but at the crux of the Uncertainty Principle is the concept that you change things by measuring them. Specifically, that you will change the very thing that you are trying to measure, simply by measuring it, and you have to admit, that’s pretty cool. The Uncertainty Principle can be fun in popular culture² but in medical research, it causes problems.

Deciding versus consenting

The consent process in medicine is serious stuff. Consent forms are fine-tuned every few years to get them just right, and often a negligence suit can hang on the consent form and consent process. Less emphasis is placed on the decision process that led to the patient signing a consent form in the first place. It turns out that the more information a patient receives, the less likely they are to ‘sign up’ for the procedure.

Book review: Stabbed in the Back

Title: Stabbed in the Back. Confronting Back Pain in an Overtreated Society (2009)

Author: Nortin M Hadler

Publisher: University of North Carolina Press

Nortin Hadler has written widely on the problems with modern medicine (overtreatment, overdiagnosis, medicalization) but he is also someone who is doing something about it, and his ideas on healthcare reform are novel, well informed, feasible and reasonable. For these though, you should read Worried Sick: A Prescription for Health in an Overtreated America. This book covers back pain; from historical, cultural, physical, social, occupational and psychological perspectives.

Health – it’s all relative

Why does Japan have the highest life expectancy and one of the best health systems, yet less than 50% of the population consider their health to be good or very good (one of the lowest scores in OECD countries)? What is health; is it the absence of a negative (disease, pain) or is it a positive concept?

Health can be measured and quantified objectively (with things like life expectancy, body mass index and blood sugar levels) or subjectively, by asking people how healthy they think they are. Objective measures provide hard data that can be useful, but they do not tell us much about how the patient perceives their own health. For this we use terms like Health-Related Quality of Life, a concept closer to things like life-satisfaction, happiness and subjective well being. It is argued that this (subjective measure) is the most important measure of health.

It turns out that self-rated health is surprisingly constant over time (despite changes in objective health), because reporting of health is relative.

Pre-operative fasting: let them eat … anything?

It is routine for patients to be fasted before an anaesthetic, usually for six hours, but for morning lists patients are usually fasted from midnight. The fasting is meant to reduce the risk of aspirating (vomit and have gastric contents enter the lungs) during the induction of anaesthesia, which can damage the lungs and be very harmful. But does fasting decrease the risk of this complication occurring? Once again, the benefits of fasting have been overestimated and the harms have been underestimated. And once again, when faced with a difficult decision, doctors have chosen the (seemingly) cautious path, and in doing so have not provided any proven benefit, and have possibly harmed patients. It may not seem like a big deal, but with over 200 million surgical procedures performed in the world each year, it can add up.

Book review: The Medicalization of Society

Title: The Medicalization of Society: On the Transformation of Human Conditions into Treatable Disorders (2007)

Author: Peter Conrad

Publisher: The Johns Hopkins University Press

Continuing the work of pioneers in medicalization such as Irving Zola and Ivan Illich, this veteran but intermittent author on medicalization gives us a sociologist’s perspective on medicalization. Conrad provides us with examples, but also gives us some causes (such as direct-to-consumer advertising, managed care, changing definitions and ‘domain expansion’) and consequences of medicalization.

Book review: How Much is Enough: Money and the Good Life

Title: How Much is Enough: Money and the Good Life (2012)

Authors: Robert and Edward Skidelsky

Publisher: Other Press, New York

This book is not about health, although it does touch on health in that our measurements of general health are intertwined with well-being and happiness. That is one justification for squeezing it into this series of book reviews. The real reason I included this book is because the authors challenge our current (economic) thinking; questioning our goals and the prevailing wisdom that guides current practice. In other words, they are skeptical.

Patient care overlooked in the concern over patient privacy

A recent journal article (paywall) had the lead-in line of:

“Patient privacy and confidentiality are being overlooked in the burgeoning use of smartphones to take medical photos”.

I argue the opposite: that ease of access to medical images has been overlooked in the concerns over privacy and confidentiality.

Cruciate ligament reconstruction: wait and see

The anterior cruciate ligament (ACL) is a major ligament deep inside the knee. It is commonly torn during sport and once torn, it usually does not heal. An ACL deficient knee is often unstable, leading to “giving way” on certain movements. Previous attempts (1960’s and 70’s) to repair the ligament did not lead to good results. Later, attempts to repair the ligament were abandoned in favour of a reconstruction in which the torn ligament is replaced with some normal tissue (part of the patella ligament or some hamstring tendons). It is a very common injury and reconstruction is a common procedure for orthopaedic surgeons. If you only want information about the procedure, there are thousands of websites that will help you. If you want to know whether the surgery is necessary, read on.

Does CPR save lives?

In TV land, most people not only survive CPR (cardiopulmonary resuscitation), but they go home from hospital and function normally afterwards (yes, they actually studied this). In reality, less than 10% survive, and for many that do, it’s not a good life. The low number of people that survive and function well after CPR (as low as 2% in some studies) leads to a question: if the results with CPR are so dismal, what would the results be if we did not do CPR? In other words: does CPR itself do anything; were those that survived going to survive anyway?

Book review: Effectiveness and Efficiency, by A Cochrane

Effectiveness and Efficiency: Random Reflections on Health Services (1972)

Author: Archibald Cochrane

Publisher: The Royal Society of Medicine Press.

Cochrane was a physician and epidemiologist whose request for an organised summary of all randomised clinical trails in medicine was answered in the form of the Cochrane Collaboration (www.cochrane.org). This classic book, written as an invited lecture, is essential reading for anyone interested in of the evolution evidence based medicine, and anyone sceptical about modern medicine. Archie Cochrane pushed for evidence based medicine before the phrase was coined.  He questioned the effectiveness of much of the (then) current medical practice (such as prolonged bed rest for heart attack patients, oral therapy for diabetes, iron for anaemia, ergotamine for migraine, and my favourite, antidepressants) and was proved right.

Reasons to operate: the ‘wobbly tripod’ of evidence

"When good evidence is lacking, the best and most dedicated of us do wrong in the utter conviction of being right"

(L. Eisenberg 1977, NEJM, 297, 1230-2)

When surgical practice varies between doctors, hospitals, regions and countries (and it does), there are many possible reasons, apart from variations in the disease or the population. Some reasons that have been given for practice variation in surgery are:

Is back fusion surgery just a placebo?

It is possible that spine fusion surgery for back pain achieves its effectiveness through the placebo effect. I would like to make the case that it is not only possible, but also probable.

Achilles tendon ruptures: let the patient decide

As we age, our collagen loses its elasticity and our tendons weaken. A ruptured Achilles tendon (TA) is often the result. This is a common injury; patients are usually aged 30 – 50 and it normally occurs with a sudden push-off during sport. Now, the initial reaction when anything is torn is to repair it, and while this holds true for inanimate objects, living things are different – 4 billion years of evolution has made some headway in that regard. Many people do not appreciate that as surgeons, when something is broken, cut or torn, all we do is put the ends roughly together and it is nature that does all the healing; we just take the credit. Placing the torn ends of a ruptured TA together is easy: you just flex the ankle. And it turns out that if you do this, and gradually bring the ankle back to normal position over a few weeks, it heals fine – without surgery, and without the complications associated with surgery.

Placebo surgery #4: Knee arthroscopy in arthritis

An arthroscopy (key hole surgery to wash out, trim or clean up) in the knee joint is one of the most common procedures in orthopaedics, and one of the most common surgical procedures overall, with over one million performed in the USA each year. An overview of arthroscopy for knee osteoarthritis can be found in a previous blog; this post covers the sham surgery trial as part of a series on that topic.

Lessons from history #3: From railway spine to whiplash

‘Railway spine’ was the name given to the widespread finding of chronic back pain and disability associated with railway injuries, and reaching near epidemic proportions in mid and late nineteenth century England. It has many similarities with other post-traumatic conditions and provides lessons about chasing physical diagnoses, and the role of psychosocial factors (in particular, the role of compensation). Lessons that we never seem to learn.

Financial incentives and surgery rates

Recently, a reader asked me if financial incentives could be responsible for the findings referred to in previous posts, like practice variations and the persistence of some surgical procedures despite evidence of their ineffectiveness. We know that you can change physician behaviour by altering financial incentives (Cochrane review), but anyone who believes in Homo Economicus will tell you that. And there is also evidence that financial incentives lead to increased health care usage amongst primary care doctors (here), but what about the evidence for financial incentives influencing surgery rates?

I'm not sick but I'm not well

This phrase got me thinking: what happens to people who do not have an identifiable disease, but still feel unwell; when the tests do not reveal any pathology, but they still have symptoms? They get a label, that’s what, because doctors cannot say: “Your tests are normal and you do not have any evidence of an underlying disease process. Further opinions and investigations are unlikely to help, and may lead to unnecessary and potentially harmful treatments”.

I don’t have time for a discourse on medicalisation, but I wanted to ask: What label do these people get? It turns out that it depends on the specialty training of the doctor that sees them.

Placebo surgery #3: Meniere's disease

Meniere’s disease is a disorder of balance (dizziness) and hearing (ringing or hearing loss). The underlying cause is not understood (idiopathic), the symptoms often fluctuate, there is crossover with other symptoms (vertigo, migraine), and there are many other conditions that cause “Meniere’s-like” symptoms. This makes the condition ripe for any treatment to look good if we think it works, due to the subjective nature of the symptoms, symptomatology that is open to misinterpretation, and the lack of any objective pathological test. Therefore, for such conditions, reporting good results from a series of patients is not enough; a more scientific (unbiased) assessment is necessary. Fortunately, somebody did just that. Unfortunately, despite the results of that study, surgery (now in many different forms) is still being used for this condition.

Stop the bleeding: questioning emergency trauma care

When trauma patients arrive at hospital with multiple injuries and haemodynamic instability (significant blood loss, low blood pressure, increased risk of dying), apart from resuscitating them (usually by giving blood and other things like clotting factors) the treatment is summed up by the phrase: “Stop the bleeding”.

“Stopping bleeding” is a biologically plausible mechanism for saving life that I will accept on face value. My question is: do our noble attempts to stop the bleeding actually influence the chance of dying? Looking at previous treatments that have fallen out of favour, I would say not. And the treatments currently in vogue are supported by as little evidence as those they replaced.

Anti-depressants make me sad

Anti-depressants have been around since the 1950’s, but it wasn’t until SSRIs (Selective Serotonin Reuptake Inhibitors), the first being Prozac, came on the market in the 1980’s that things really took off. The safer profile meant that primary care physicians could start prescribing, and Prozac itself became a blockbuster drug (over $US1 billion in annual sales) and a household name. Others followed and by 2005, anti-depressants were the most prescribed drugs in the USA. For most patients, however, they are no better than placebo. That doesn’t mean that they don’t’ work, they just don’t work any better than placebo.

Book review: Between the Lines

Prostatectomy: doctors just don’t get it.

The results from the latest randomised trial comparing prostatectomy to non-operative treatment for prostate cancer are all over the news, but what caught my eye was the response from a senior clinician in my country. I will address his comment, and a related comment, below.

The study (here) recruited 731 men less than 75 years of age and found that the overall mortality after 10 years was 47% in the surgical group and 50% in the non-operative group. The difference was not statistically different. If it were, you would have to weigh that benefit against the 88% erectile dysfunction and 17% incontinence rates in the surgical group (2 -3 times higher than the non-operative group).

“The whole problem is selecting the ones which need to be operated on”

Manual handling techniques and back pain

Walking from the change rooms to the operating theatres, I go past a series of posters using drawings of animals in funny positions, extolling the virtues of manual handling techniques. Lifting with your knees, bending with your hips, twisting with your elbows, or whatever. And when I arrive in the operating rooms, I am regularly fascinated by the addition of yet another ingenious device to move a patient less than one metre from their bed to the operating table. Last week we used something that was basically a fully functioning hovercraft (here).

There are countless well-meaning guidelines (and rules) on how we should be moving objects (like this, and this) but do they help? I lift a lot of heavy things in awkward positions when I am working in the yard, but really only get back pain when I lie on my back for too long. I see Olympic weight lifters putting a fair bit of weight through their back without much back pain, and I know that the biggest predictors of back pain in the workplace are not physical factors (try this, this and this) but things like job satisfaction. What is the evidence that this advice, or these devices, actually work?

Why placebo surgery is ethical, and necessary

The research discussed in my previous post on placebo surgery for Parkinson’s disease sparked a rush of publications debating the ethics of placebo surgery, even before the results were released. One of these articles (here) gives a good overview of the ethics of placebo (sham) surgery controls, using one of the Parkinson’s trials as its case in point. The authors give both sides of the argument, but I disagree with two important points; points that lead them to conclude that placebo surgery is not necessary.

Placebo surgery #2: Surgery for Parkinson’s disease

In Parkinson’s disease, there is insufficient dopamine in parts of the brain. This chemical can be replaced in pill form, but with variable effect, and with some side effects. In the 1990’s many clinics were transplanting dopamine-producing cells from embryos into the brains of people with Parkinson’s disease. This procedure involved drilling holes in the skull, through which the cells were inserted. Animal studies showed that the cells could survive, and that the procedure could correct some of the movement disorders.  Open label trials (no placebo) of these transplants in humans showed that patients improved. This is the same evidence base for many operations performed today: a biological mechanism, supportive lab studies, and reports of patients that got better. Enter, the sham.

Placebo surgery #1: Surgery for angina

I will attempt to write a short note on every clinical study that has compared surgery to a placebo operation (sham surgery). The common thread is that while many patients improve after the real operation, many patients also improve after the sham operation, and in each example the real operation is no more effective than the sham surgery. This shows that when we see patients get better after we treat them, it is not necessarily due to the specific effect of our treatment. We (the doctors and the patients) perceive effectiveness by attributing cause and effect to the association we see. The difference between the perceived effect and the specific (real) effect is the placebo effect.

This study dates from 1959, and relates to a surgical procedure for angina that dates from 20 years before that: internal mammary artery ligation.

Lessons from history #2: Evidence based blood letting

Objections to evidence based medicine (a scientific approach to medicine) by doctors often sound like this:

“Practicing physicians are unwilling to hold their decisions in abeyance till their therapies received numerical approbation. Further, they are not prepared to discard therapies validated by both tradition and their own experience on account of somebody else's numbers.”

Things have not changed.

These quotes are from the early 1800’s and express the attitude of physicians at that time to studies such as the landmark paper in the American Journal of Medical Sciences from 1836. The article (by PCA Louis) systematically pooled data from many patients and used statistics to look at the effectiveness of blood letting for pneumonia (then standard practice). It found the treatment to be ineffective.*

Steroid injections for low back pain

The Cochrane review on injections for low back pain concludes: “There is insufficient evidence to support the use of injection therapy in subacute and chronic low-back pain”. The injections contain corticosteroid (‘steroids’, ‘cortisone’) mixed with local anaesthetic and are injected into the epidural region or the facet joints of the lumbar spine. The injections have been compared to placebo injections and to other treatments and, without going in to all the detail, they basically don’t work.

Prolotherapy: the illusion of effectiveness

Many of my blogs have a recurring theme: an intervention that sounds great (biologically plausible), has great early results, but on rigorous scientific testing is shown to be ineffective. Prolotherapy does not fit that mould, because I don’t even buy the biological argument in the first place. Prolotherapy involves the injection of irritant solutions in order to strengthen tissues and relieve pain. That makes about as much sense as homeopathy, or being struck on the head to relieve a headache.

The squeaky joint gets the oil: lubricants for osteoarthritis

Hyaluronic acid (HA) is the lubricant that normally oils your joints. In osteoarthritis of the knee, the joints are stiff and painful, and there is less of this lubricant in the joint. So why not inject HA directly into the joints (viscosupplementation)?  Talk about biological plausibility. To many people, this must be very appealing. We know this because people around the world have paid hundreds of millions of dollars to have this stuff injected into their knees. And yet the latest review of the research concludes that HA injections do not provide any significant benefit and may increase the risk of harm. So how do they conclude that, when so many individual studies show that it works? Because the studies are biased.

The parachute analogy

“You don’t need a randomised trial to prove that parachutes work” is a common refrain from doctors who believe that their operation works, despite a lack of good scientific evidence from controlled trials. They see it as an argument-stopper, but it is actually an example of argument by analogy, and a poor one at that. And at least one surgeon has been burned by putting the parachute analogy in writing.

Knee arthroscopy in arthritis: an evidence-practice mismatch

Osteoarthritis, where the cartilage lining a joint gets worn down, is common (Australian data, UK data, US data). Most people will get it if they live long enough, and the knee joint is commonly affected. There is little that can be done to repair or reverse this process, and a related paper that covers many osteoarthritis treatments shows that most of the things we do (analgesics, anti-inflammatory medication, injections etc.) only provide temporary relief, and many of them hardly work at all. Treatment, if severe enough, often means a knee replacement.

Knee replacement surgery is major surgery so it is only reserved for those with severe osteoarthritis. So what do surgeons do with patients who have knee pain and mild or moderate arthritis? They often do an arthroscopy: a low risk, day-only procedure that pays well and seems to work some of the time. Hundreds of thousands are done in the US every year, and in my state the rate of arthroscopy is high and is rising.

The trouble is: it doesn’t work. Most patients still have pain, some get worse, and about 20% will end up having a knee replacement within 2 years anyway. Feel free to skip to the last paragraph for the Bottom Line, or read on for the details.

Platelet Rich Plasma continues to unimpress

Further to my previous blog post on Platelet Rich Plasma (PRP), a recent review of five clinical trials of its use in rotator cuff repair surgery of the shoulder concluded:

"PRP does not have an effect on overall retear rates or shoulder-specific outcomes after arthroscopic rotator cuff repair."

And a systematic review of PRP in orthopaedic surgery concluded: 

"there is uncertainty about the evidence to support the increasing clinical use of platelet-rich plasma and autologous blood concentrates as a treatment modality for orthopaedic bone and soft-tissue injuries"

The scientific evidence for PRP's lack of effect builds, while its clinical use increases.

Doctors doctoring the research: fraud and error

I have been reading about publication retractions. They are scientific-speak for “Whoops”. This can either mean “Whoops, I made a mistake” (error), or “Whoops, you caught me” (fraud). It is sometimes hard to distinguish between them. Either way, it is another example of published research that is wrong, and it looks like there is little we can do to stop it.

How big is the problem? Why does it matter? Why does it happen? and How can we stop it?

How big is the problem?

The extent of the problem on an individual level can be seen on the Retraction Watch blog, but is best illustrated by the case of Dr Fujii, an anaesthetist from Japan who currently holds the record for the number of articles retracted (nearly 200), which is more than I have ever had published. But as he has not admitted any wrongdoing, we don’t know whether he is fraudulent, or whether he is a doctor who makes a LOT of mistakes. I am not sure which is worse.

Forget the pre-game stretch

Another example of something that sounds good, but isn’t. How many people in the world swear by their pre-game stretches? Or post-game stretches? Especially when there is so much evidence to the contrary.

Skeptic or cynic?

I am a skeptic, and I try not to be a cynic. Skeptics accept the scientific method and rational thinking as the best tools with which to evaluate claims and get closest to the truth. Skeptikos in Greek means to inquire, or find out. This can be hard work; being a cynic is easy.

Invasion of the robots

In my institution, the surgeons are keen to get some government money to turn us into a robotic surgery centre. I fear they are doing it for the reputation and the referrals, but this would be cynical rather than skeptical (see upcoming blog on the difference). So I will simply say that they are not doing it to benefit the patients. They may think they are, but I am not aware of any evidence that patient-based outcomes are better with robotic surgery. I am however, aware of empirical evidence that robots cost a lot, because I have seen the bill.

It turns out that robotic surgery is yet another example of something that sounds good, with some research showing improvements in some aspects, but with the whole thing falling down when it comes to improving patient health.

The MS cure, that isn't

A surgeon in Italy has developed an operation to treat MS (multiple sclerosis), based on a biological plausible theory, and he has reported good results after the treatment. As readers know, this is usually enough to get an operation accepted, and it is the only support behind many current operations. Readers should also know that these criteria do not provide proof of effectiveness. In this story though, it is the patients who have pushed for this treatment to be available.

Are doctors as good as they think they are?

Benjamin Spock, the American paediatrician, once said: “Trust yourself. You know more than you think you do”. That may be good advice for patients, but the opposite holds for doctors. We know that doctors overestimate the effectiveness of their treatments (a major theme of this blog), but it turns out that there is also a gap between their perceived knowledge of medicine and their actual knowledge. If you ask doctors how competent they are on a particular medical topic or skill (a subjective assessment) and then sit them down and test them on the same topic or skill (an objective assessment), you find a significant and consistent pattern: doctors think they are a lot better than they actually are. And it appears that surgeons (here and here) are not excluded.

Overdiagnosis: providing a solution when there is no problem

I just complain about it; these people are doing something about it. Overdiagnosis occurs when people who are healthy are diagnosed with a disease that will not ultimately harm or kill them. It is associated with over-medicalisation and leads to overtreatment and the associated risk of harm. It is a classic example of our tendency to assume that the more tests and treatments we get, the healthier we become. Often it is the opposite.

Don’t believe the hype, or the research

I spend a lot of time telling people to look for the rational, scientific evidence and to try to avoid the hype from marketers and doctors. But it seems that you can’t always believe the scientific evidence either, judging from quotes like this one from Marcia Angell, the former editor of the most respected and highly ranked medical journal in the world – the New England Journal of Medicine.

“It is simply no longer possible to believe much of the clinical research that is published, or to rely on the judgment of trusted physicians or authoritative medical guidelines. I take no pleasure in this conclusion, which I reached slowly and reluctantly over my two decades as an editor of The New England Journal of Medicine”

Lessons from history #1: The stress of modern life

Is the hustle and bustle of modern life causing you stress? Can’t cope with the constant barrage on your senses? Having trouble keeping up with the pace of advancement in science and technology? Then you are not alone. Here is a quote from an article in Scientific American highlighting the very problem. The thing is, it was written over 100 years ago.

“To point to the stress and hurry of modern city life as the cause of half of the ills people suffer today has become commonplace.

While we may imagine future generations of people perfectly calm among a hundred telephones and sleeping sweetly while airships whiz among countless electric wires over their heads and a perpetual night traffic of motor cars hurtles past their bedroom windows. As yet, our nervous systems are not so callous.”

                                                                                                                    (Scientific American, 1902)

Vertebroplasty and the 'decline effect'

The favourable results of treatments can fade over time (the Decline Effect, see later post) for many reasons. Often the initial enthusiasm (bias) of the proponents is not replicated in later studies (see previous blog). But sometimes it can be shown that as the scientific validity of the studies improve, the effect decreases. This is because studies with better scientific methods will (by definition) have less bias (causes of error) and therefore the results will provide a better estimation of the truth. Vertebroplasty (injecting osteoporotic vertebral fractures with cement) is a recent (and controversial) case in point.

Are you getting your money’s worth from surgery?

There is a common belief that if something costs more, it must be better; that you get what you pay for. Recently, a friend of a friend (this is not sounding very scientific, but hear me out) went to see two spine surgeons about his neck pain. One surgeon advised against surgery. The other recommended a neck fusion, to be done in the private hospital with an out-of-pocket “gap” (the fee, above and beyond the health fund rebate) of $10,000. He is now considering drawing on his retirement fund to pay for the surgery. Considering that there are surgeons who will perform this operation for no “gap”, is this worth it? Is the price a reflection of quality?

Appendicitis - is surgery necessary?

There is one thing (out of a list of many) that makes me disappointed with a surgical trainee; it comes after they describe a new case to me and offer their preferred surgical treatment. I then ask them for the evidence supporting their recommendation. They say: “Well, I saw a guy do one once.” This short statement says so much. Firstly, how we are influenced by what we see, particularly when somebody considered to be senior or authoritative does it. It also shows how readily we recommend treatments without good knowledge of the outcomes of that treatment, or of the alternatives. It is easier just to think: “If this guy did it, then it must be OK”.

This is why appendicectomy is so commonly done. Randomised trials have told us that removing the appendix is not necessary on first presentation, and it is associated with a worse long term outcome. Yet if you present to any of my hospitals with suspected appendicitis, you are unlikely to be leaving hospital without having your appendix removed.

Stop attacking my heart

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The idea behind "revascularising" coronary arteries is very appealing: “My blood vessels were blocked and the doctors unblocked them”. Like so many things addressed in my blog, this sounds good and seems hard to argue with, unless you look at it scientifically and ask the right questions. ...

Not such a great IDET

IDET (Intradiscal electrothermal therapy) fits perfectly into the template for a successful placebo treatment described in my earlier blog. It has everything: biological plausibility, high tech equipment, high cost, conflicts of interest, great lab results, encouraging results from early clinical studies, and no advantage over placebo...

Cancer screening part 2: PSA for prostate cancer

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For the boys, prostate cancer screening is another case in point. Screening is easy (just a blood test - a PSA) but like all screening programs it is plagued by overdiagnosis, and the harms from treatment for this condition are also quite significant (high rates of incontinence and erectile dysfunction).

Cancer screening part 1: mammography

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Cancer screening is a no brainer for most people, who think: “why wouldn’t you do it?” It turns out that there are lots of reasons why you wouldn’t do it; reasons that (of course) fall under the all too familiar heading of Overestimating the Benefits and Underestimating the Harms. Time to take a look at the risk-benefit balance.

RF: a harmful placebo

RF (Radio Frequency, or Radio Frequency Ablation) is used widely. The idea is that a probe is inserted into the affected area which then emits a radio frequency that “changes” (read: damages) the local tissues. It is used in the spine, the shoulder, the wrist and even for liver tumours.

The story with this is so similar to my previous blogs that many of you may be able to fill in the rest of this one for me. In fact, for things like this I should develop a standard blog template to cut and paste in the future. Something like this:

Conflict of Interest, or Concordance of Interests.

My last blog on ultrasound and fracture healing brought up the topic of authors with conflicts of interest. This is where the authors have something to gain from publishing favourable results of medical therapies; benefits that might include royalties, stock options, research funding and my favourite: consultancy fees (this is fancy term for a relatively simple process whereby a company gives money to a doctor, often large amounts and at regular intervals). Sometimes the authors are direct employees of the company making the device or drug in question. And sometimes these employees write the article for the esteemed senior author to put his or her name to (ghost writing), thereby giving the article authority.

Does ultrasound make bones heal? No.

The acronyms are getting bigger. LIPUS (Low Intensity Pulsed Ultrasound) therapy is commonly used to heal fractures faster, or to get them to heal when they have not. It is a machine that straps on to the limb and is worn for minutes or hours each day, for a few weeks or months. Just like the techniques in my recent posts, it costs several thousand dollars and people assume that if it costs that much and is high-tech, it must be working. Lets cut to the chase.