This week, a question of evidence and some news.
How do we know that the surgical removal of the lump is the best way to treat primary breast cancer? Or that removing the lump is the best way to treat primary bowel cancer? Truth is, there is not much research evidence for either.
A Professor of bowel surgery assured me that there has never been a research trial conducted to test the bowel cancer operation. My guess is the same applies for breast cancer. The experiment would require randomising two groups of people with similar types of cancer, operating on one group, leaving the other, and waiting to find out what happens.
Actually, the real experiment would be to anaesthatise everyone in the study, make the same surgical skin incision in everyone, but then only remove the offending lump in half, before sewing up the skin for everyone. Then wait to find the result. That would be a fair research experiment to evaluate whether surgery was the best way to treat the condition.
Now, we can probably imagine the reaction of an ethics Committee faced with a proposal to conduct such an experiment! We can be almost sure it will never happen.
But then, these days we hear so much about the need for the practice of medicine to be “evidence based”, and how this evidence base sets modern western medicine apart from unproven alternatives.
So if the is no clear research base for such important medical interventions as the primary treatment of breast and bowel cancer, what is going on? Let us go Out on a Limb and attempt to make sense of all this.
Firstly it will be helpful to understand what Evidence Based Medicine (EBM) really is. The accepted definition was laid out in the British Medical Journal in 1996 and states “EBM is the conscientious and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research. By individual clinical expertise is meant the proficiency and judgment that individual clinicians acquire through clinical experience and clinical practice”.
Here is the key. EMB involves research AND clinical experience. Where some people become confused is that they only value the research. So while there is little if any research to support primary surgery for breast and bowel cancers, there is a huge body of clinical experience that has led everyone to believe the surgery to be the correct treatment.
The devaluing of clinical experience in some quarters is exacerbated in my view by the position it holds in the hierarchy of evidence. In medicine, this hierarchy of evidence is put forward by the NHMRC (the National Health and Medical Research Council) and it goes like this:
The NHMRC levels of evidence relevant to the validation of medical research.
Level l: from a systematic review of all relevant randomised controlled trials – meta-analysis.
Level 2: from at least one properly designed randomised controlled clinical trial.
Level 3a: from well-designed pseudo-randomised controlled trials (alternate allocation or some other method).
Level 3b: from comparative studies (including systematic reviews of such studies) with concurrent controls and allocation not randomised, cohort studies, case-control studies, or interrupted time series with a parallel control group.
Level 3c: from comparative studies with historical control, two or more single-arm studies or interrupted time series without a parallel control group.
Level 4: opinions of respected authorities based on clinical experience, descriptive studies or reports of expert committees.
Level 5: represents minimal evidence that represents testimonials.
In some versions, Level 5 is not included, either way, clinical experience is down the bottom, while meta-analysis of multiple research trials is right at the top.
Now let us be clear. This hierarchy is well founded and the intention is to give us the facts. The intention is to avoid errors in judgment, misunderstandings, stupidity, bad habits, even superstition.
Problem is, so much of current medicine is based on the evidence gathered through experience, rather than research. The primary treatment of breast and bowel cancer would seem to be based on Level 4 evidence – clinical experience.
Paul Smith recently wrote in Australian Doctor “During the numerous interviews for Australian Doctor's series on alternative medicines over the past few weeks, the conversations with academics from both sides of the debate often ended up pointing in one direction -- the holes in the evidence base for medicine.
"Aged care is a good example: the lack of robust, decent-sized trials that give clear conclusions about effects of multiple medications for multiple comorbidities in a population a few years away from death. You can also mention, as one retired pharmacologist did, the almost blanket use of SSRIs for mild depression. Then comes PSA screening.
A deeper point was made by Queensland GP, Dr Nanu Grewal a few years ago, when he sparked a heated debated in the pages of Australian Doctor for suggesting that, at its "most absolutist", evidence-based medicine was "a form of zealotry" that failed to recognise real-life patients in all their confounding non-evidence-based complexity.
"Our EBM specialist tells a patient that 14 published double-blind, multi-centre, peer-reviewed, randomised, longitudinal, controlled trials have shown that drug X is useless in treating the patient's arthritis," he wrote. "The patient turns and says: 'But X makes me feel better.' Does this make the patient a knave and a fool?"”
Much of the debate around EBM recently has focused on Conventional and Alternative Medicine. What about Lifestyle Medicine? What about meditation and therapeutic nutrition?
Well, actually, there may well be more research evidence to support the therapeutic benefits of meditation than many common procedures carried out in the average GP’s rooms. Well over 4,000 scientific studies have been printed in medical journals all around the world and attest to meditation’s positive benefits for a wide range of physical and psychological conditions. You can access this research in a great, free website that is updated regularly – see below.
When it comes to nutrition and cancer, there is a sad lack of quality research. Maybe, in this field, clinical evidence is still the main tool for assessing what to do. In that case, the 30 years of experience built up by myself and others at the Gawler Foundation, following working closely with so many people for so many years, may well provide one of the biggest bodies of evidence available.
So what sense do we make of all this? How do we decide what to do with the medical choices that face us all from time to time?
Firstly, appreciate that in some ways EBM is a peculiar term to accentuate . Everyone decides what to do according to the evidence available. Perhaps what EBM is really aiming to do is to take emotion and ignorance out of the equation, but then if it overly emphasizes research and de-emphasizes experience, it will either drastically limit what is permissible, or miss out on important possibilities.
And what of intuition? In my days as a veterinarian, I contend quite a deal of what I did was intuitive. Maybe that intuition was based on knowledge and experience, but it sure felt like intuition to me. You do not hear much about intuition being taught in the veterinary or medical schools.
Perhaps as patients this provides us with the real answer. Find a practitioner you can trust. Choose them on the best evidence you value. Is that knowledge? Personal recommendation? Intuition? Whatever works for you. Listen to their advice. Ask what they would recommend. What about if they were treating themselves or their beloved? What would they do or recommend then?
Take their advice and test it against your own sensibilities. Does it make sense? Do you trust the advice? Do you need a second opinion?
When you feel confident enough to commit, then commit. Give whatever you do your best shot and expect the best. More power to you and may you decide wisely!
1. People from the Brisbane workshops who indicated that they would like to be added to the database still do need to click on to the confirmation email sent last week to be included.
2.Thanks to everyone who took part in the recent survey, the results have been very informative. About half of you said you like the blog weekly, half fortnightly or monthly. As it has been weekly since inception, and as I am rewriting “You Can Conquer Cancer” at the moment, I will go to fortnightly for the next little while.
3. Had a great weekend presenting Health, Healing and Wellbeing” in Shepparton. Lovely to meet up with some people who came to workshops I gave nearly 30yrs ago, as well as people from old groups and quite a bunch of new people.
4. The new book “The Mind that Changes Everything” has arrived and is now available, either from bookshops or via the web - click below for details.
5. Workshops coming up soon in Melbourne, Darwin, Bunbury and Perth - click below for details.
NHMRC Levels of Evidence
Meditation Research - an up to date bibliography via IONS (The Institute of Noetic Sciences)
The Mind that Changes Everything
Meditation - How much is enough?