A recent comment to a blog-post about alternative treatments for cancer inspired me to ponder a bit. I think it is noteworthy because it exemplifies so many of the comments I hear in the realm of alternative medicine on an almost daily basis. Here is the comment in question:
“Yes…it appears that the medical establishment have known for years that chemotherapy a lot of the time kills patients faster than if they were untreated…what’s more, it worsens a person’s quality of life in which many die directly of the severe effects on the endocrine, immune system and more…cancers often return in more aggressive forms metastasising with an increased risk of apoptosis. In other words it makes things worse whereas there are many natural remedies which not only do no harm but accumulating evidence points to their capacity to fight cancer…some of it is bullshit whilst some holds some truth!! So turning away from toxic treatments that kill towards natural approaches that are showing more hope with the backing of trials kinda reverses the whole argument of this article.”
The comment first annoyed me a bit, of course, but later it made me think and consider the differences between conspiracy theories, assumptions, opinions, evidence and scientific facts. Let’s tackle each of these in turn.
A conspiracy theory is an explanatory or speculative theory suggesting that two or more persons, or an organization, have conspired to cause or cover up, through secret planning and deliberate action, an event or situation typically regarded as illegal or harmful.
Part of the above comment bears some of the hallmarks of a conspiracy theory: “…the medical establishment have known for years that chemotherapy a lot of the time kills patients faster than if they were untreated…” The assumption here is that the conventional healthcare practitioners are evil enough to knowingly do harm to their patients. Such conspiracy theories abound in the realm of alternative medicine; they include the notions that
- BIG PHARMA is out to kill us all in order to maximize their profits,
- the ‘establishment’ is suppressing any information about the benefits of alternative treatments,
- vaccinations are known to be harmful but nevertheless being forced on to our children,
- drug regulators are in the pocket of the pharmaceutical industry,
- doctors accept bribes for prescribing dangerous drugs
- etc. etc.
In a previous blog-post, I have discussed the fact that the current popularity of alternative medicine is at least partly driven by the conviction that there is a sinister plot by ‘the establishment’ that prevents people from benefitting from the wonders of alternative treatments. It is therefore hardly surprising that conspiracy theories like the above are voiced regularly on this blog and elsewhere.
An assumption is something taken for granted or accepted as true without proof.
The above comment continues stating that “…[chemotherapy] makes things worse whereas there are many natural remedies which not only do no harm but accumulating evidence points to their capacity to fight cancer…” There is not proof for these assertions, yet the author takes them for granted. If one were to look for the known facts, one would find the assumptions to be erroneous: chemotherapy has saved countless lives and there simply are no natural remedies that will cure any form of cancer. In the realm of alternative medicine, this seems to worry few, and assumptions of this or similar nature are being made every day. Sadly the plethora of assumptions or bogus claims eventually endanger public health.
The above comment continues with the opinion that “…turning away from toxic treatments that kill towards natural approaches that are showing more hope with the backing of trials kinda reverses the whole argument of this article.” In general, alternative medicine is based on opinions of this sort. On this blog, we have plenty of examples for that in the comments section. This is perhaps understandable; evidence is usually in short supply, and therefore it often is swiftly replaced with often emotionally loaded opinions. It is even fair to say that much of alternative medicine is, in truth, opinion-based healthcare.
One remarkable feature of the above comment is that it is bar of any evidence. In a previous post, I have tried to explain the nature of evidence regarding the efficacy of medical interventions:
The multifactorial nature of any clinical response requires controlling for all the factors that might determine the outcome other than the treatment per se. Ideally, we would need to create a situation or an experiment where two groups of patients are exposed to the full range of factors (e. g. placebo effects, natural history of the condition, regression towards the mean), and the only difference is that one group does receive the treatment, while the other one does not. And this is precisely the model of a controlled clinical trial.
Such studies are designed to minimise all possible sources of bias and confounding. By definition, they have a control group which means that we can, at the end of the treatment period, compare the effects of the treatment in question with those of another intervention, a placebo or no treatment at all.
Many different variations of the controlled trial exist so that the exact design can be adapted to the requirements of the particular treatment and the specific research question at hand. The over-riding principle is, however, always the same: we want to make sure that we can reliably determine whether or not the treatment was the cause of the clinical outcome.
Causality is the key in all of this; and here lies the crucial difference between clinical experience and scientific evidence. What clinician witness in their routine practice can have a myriad of causes; what scientists observe in a well-designed efficacy trial is, in all likelihood, caused by the treatment. The latter is evidence, while the former is not.
Don’t get me wrong; clinical trials are not perfect. They can have many flaws and have rightly been criticised for a myriad of inherent limitations. But it is important to realise that, despite all their short-comings, they are far superior than any other method for determining the efficacy of medical interventions.
There are lots of reasons why a trial can generate an incorrect, i.e. a false positive or a false negative result. We therefore should avoid relying on the findings of a single study. Independent replications are usually required before we can be reasonably sure.
Unfortunately, the findings of these replications do not always confirm the results of the previous study. Whenever we are faced with conflicting results, it is tempting to cherry-pick those studies which seem to confirm our prior belief – tempting but very wrong. In order to arrive at the most reliable conclusion about the efficacy of any treatment, we need to consider the totality of the reliable evidence. This goal is best achieved by conducting a systematic review.
In a systematic review, we assess the quality and quantity of the available evidence, try to synthesise the findings and arrive at an overall verdict about the efficacy of the treatment in question. Technically speaking, this process minimises selection and random biases. Systematic reviews and meta-analyses [these are systematic reviews that pool the data of individual studies] therefore constitute, according to a consensus of most experts, the best available evidence for or against the efficacy of any treatment.
Some facts related to the subject of alternative medicine have already been mentioned:
- chemotherapy prolongs survival of many cancer patients;
- no alternative therapy has achieved anything remotely similar.
The comment above that motivated me to write this somewhat long-winded post is devoid of facts. This is just one more feature that makes it so typical of the comments by proponents of alternative medicine we see with such embarrassing regularity.