“…at the heart of science is an essential balance between two seemingly contradictory attitudes – an openness to new ideas, now matter how bizarre or counterintuitive, and the most ruthlessly sceptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense.”
Evidence-based medicine has revolutionized medical practice, transforming it from an industry of charlatans and incompetents into a system of healthcare that can deliver such miracles as transplanting kidneys, removing cataracts, combating childhood diseases, eradicating smallpox and saving literally millions of lives each year.”
Simon Singh & Edzard Ernst
I have just finished reading Simon Singh and Edzard Ernst’s excellent book, Trick or Treatment: The Undeniable Facts About Alternative Medicine. This book demonstrates the value of ‘scientific thinking’ for real life. Singh is a best-selling author and science journalist, while Ernst is a professor of complementary medicine at the University of Exeter and author of The Oxford Handbook for Complementary Medicine.
In their book, Ernst and Singh examine in depth four common alternative medicine treatments: acupuncture, homeopathy, chiropractic therapy, and herbal medicine (they also have an appendix that provides one page summaries of their conclusions for 36 other forms of alternative medicine). Their goal is to take as critical and unbiased a look as possible at alternative medicine therapies and determine their actual effectiveness and safety. As a professor of complementary medicine, Ernst might be expected to have a bias in favour of alternative medical therapies, but he has a thoroughgoing commitment to following where the best evidence leads.
The first chapter of the book is entitled, “How do you determine the truth?” The focus of this chapter is on the discovery and development of the practice of controlled clinical trials. The authors point out that prior to the invention of this technique for evaluating the true effectiveness of medical interventions, more people died under the treatment of doctors than were helped. The history of blood letting as a cure-all intervention is a case in point that they describe in detail, noting that it was probably bloodletting that killed George Washington! Bloodletting was standard practice and was based on a faulty understanding of human physiology — the four ‘humours’ — that had been believed for centuries.
Interestingly, the first real “clinical trial” that we know of led to the discovery of citrus fruit as a cure for scurvy in the mid 1700s. Although initially scoffed at by many of his peers, James Lind, the man who discovered this cure, seems to have been the first to conduct an actual controlled study. Ultimately, his evidence overcame the prejudice of other doctors and, once the practice became widespread, the distribution of fruit or lemon juice on ships ended the devastation brought by scurvy. A second early example of a formal clinical trial took place in the early 1800s, where this new approach was applied to the practice of bloodletting. In this case, Alexander Hamilton proved conclusively that bloodletting was not only ineffective against the conditions for which it was applied, but that the death rate for those who received this treatment was 10 TIMES that of those who did not!
Slowly, the practice of evidence-based medicine began to become the norm. And this has been a major boon for all. Ernst and Singh point out:
Prior to the clinical trial, a doctor decided his treatment for a particular patient by relying on his own prejudices, or on what he had been taught by his peers, or on his misremembered experience of dealing with a handful of patients with a similar condition. After the advent of the clinical trial, doctors could choose their treatment for a single patient by examining the evidence from several trials, perhaps involving thousands of patients. There was still no guarantee that a treatment that had succeeded during a set of trials would cure a particular patient, but any doctor who adopted this approach was giving his patient the best possible chance of recovery…. The clinical trial helped give birth to modern medicine, which has enabled us to live longer, healthier, happier lives.
In this chapter, the authors make three key points related to my topic of why scientific thinking is good for everyone, not just scientists when it comes to determining what medical therapies you and I should use.
First, even when we don’t understand all the mechanisms behind why a particular medical intervention works, the emphasis in evidence-based medicine is primarily on whether or not a particular medical therapy actually works (as opposed to a positive outcome being either the result of a placebo effect or simply the natural course of healing for a particular illness or disease) and whether or not it is safe. This suggests that the results of good evidence-based research should be taken very seriously, because the results are concerned with whether or not the medical intervention being studied actually works or not. It’s not about what the researchers think of the philosophy behind the intervention. It’s about whether or not that intervention works and is safe. Using medical therapies that have not been well tested means you are using something that may not actually work and may not be safe. Natural does not necessarily mean safe (remember it was ‘natural’ hemlock that Socrates swallowed to kill himself!).
Second, the methodology of the study matters greatly. There are several criteria for establishing validity for the results of a medical study. One is that it be a controlled study, meaning that separate groups of patients are treated similarly except for the item being tested. This is done to rule out / minimize other possible factors that could influence patient outcomes (for example, if one group is treated by a caring doctor in a pleasant surrounding and the other is treated by a grump in a sterile lab, the possibility of different placebo effects from the therapeutic relationship taints the results). Another factor is that it be randomized. In other words, participants in the different groups need to be assigned on a random basis. Yet another factor is that the study be double-blinded. This refers to the fact that the patients being tested do not know if they are being given the real intervention or a placebo and the researchers do not know whether they are administering the real intervention or a placebo. Other studies of the placebo affect tell us that even if a patient is unaware that they are being given the “real” treatment, if the one administering it knows, their non-verbals are often very different than if they are administering a placebo. The impact of that non-verbal language has been found to have a strong influence on creating a placebo effect. The last factor for determining the validity of a study’s results is the size of the study. If there is a very small number of individuals being used, it is very hard to determine if the results are truly significant or merely chance.
When evaluating a study of any medical therapy (conventional or alternative) it is important to determine if these critieria have been met. Studies that do not meet them are generally not very reliable. The more these criteria are demonstrated to have been met, the more we can rely on the results. It is important to note that pharmaceuticals do have to meet these criteria in order to be approved by the FDA in the States and Health Canada in Canada. Alternative medicine (homeopathic and herbal remedies) do not. Fortunately, many alternative therapies are now being subjected to well-designed studies that do meet these criteria. Singh’s and Ernst’s book discusses the results of those studies.
Third, the medical field is open to new therapies that work, wherever they arise from. As the authors point out, had the term ‘alternative medicine’ been in existince when James Lind did his study on scurvy, oranges and lemons might well have been labeled as such, as they were natural remedies that were not backed by a plausible theory. But the evidence was ultimately incontrovertible. Only much later did the biology explaining the relationship between scurvy and vitamin C deficiency arise. While there may be a natural tendency for many individual doctors to resist new therapies, ultimately, evidence triumphs. So, alternative medicine becomes conventional medicine when it is demonstrated through controlled studies to be both effective and safe. There is no medical conspiracy against alternative medicine. It is simply the demand that alternative therapies be evaluated through controlled studies that is the issue.
The upshot of this is that if we want to avail ourselves of the very best treatments (conventional or alternative) it is important to use scientific thinking, particularly in demanding and evaluating well-designed controlled studies that provide evidence of a treatment’s efficacy and safety.
To do otherwise can lead to:
- a waste of money (both your own and government subsidies).
- settling for only a placebo effect (when you could have a real effect from a proven intervention and the placebo effect on top of it!).
- possible harm to oneself or those who you take for treatment.
I encourage your to read Singh’s and Ernst’s book and to apply scientific thinking to all medical practices — conventional and alternative alike.