This post is dedicated to Mel Koppelman.
Those who followed the recent discussions about acupuncture on this blog will probably know her; she is an acupuncturist who (thinks she) knows a lot about research because she has several higher qualifications (but was unable to show us any research published by herself). Mel seems very quick in lecturing others about research methodology. Yesterday, she posted this comment in relation to my previous post on a study of aromatherapy and reflexology:
Professor Ernst, This post affirms yet again a rather poor understanding of clinical trial methodology. A pragmatic trial such as this one with a wait-list control makes no attempt to look for specific effects. You say “it is quite simply wrong to assume that this outcome is specifically related to the two treatments.” Where have specific effects been tested or assumed in this study? Your statement in no way, shape or form negates the author’s conclusions that “aromatherapy massage and reflexology are simple and effective non-pharmacologic nursing interventions.” Effectiveness is not a measure of specific effects.
I am most grateful for this comment because it highlights an issue that I had wanted to address for some time: The meanings of the two terms ‘efficacy and effectiveness’ and their differences as seen by scientists and by alternative practitioners/researchers.
Let’s start with the definitions.
I often use the excellent book of Alan Earl-Slater entitled THE HANDBOOK OF CLINICAL TRIALS AND OTHER RESEARCH. In it, EFFICACY is defined as ‘the degree to which an intervention does what it is intended to do under ideal conditions. EFFECTIVENESS is the degree to which a treatment works under real life conditions. An EFFECTIVENESS TRIAL is a trial that ‘is said to approximate reality (i. e. clinical practice). It is sometimes called a pragmatic trial’. An EFFICACY TRIAL ‘is a clinical trial that is said to take place under ideal conditions.’
In other words, an efficacy trial investigates the question, ‘can the therapy work?’, and an effectiveness trial asks, ‘does this therapy work?’ In both cases, the question relate to the therapy per se and not to the plethora of phenomena which are not directly related to it. It seems logical that, where possible, the first question would need to be addressed before the second – it does make little sense to test for effectiveness, if efficacy has not been ascertained, and effectiveness without efficacy does not seem to be possible.
In my 2007 book entitled UNDERSTANDING RESEARCH IN COMPLEMENTARY AND ALTERNATIVE MEDICINE (written especially for alternative therapists like Mel), I adopted these definitions and added: “It is conceivable that a given therapy works only under optimal conditions but not in everyday practice. For instance, in clinical practice patients may not comply with a therapy because it causes adverse effects.” I should have added perhaps that adverse effects are by no means the only reason for non-compliance, and that non-compliance is not the only reason why an efficacious treatment might not be effective.
Most scientists would agree with the above definitions. In fact, I am not aware of a debate about them in scientific circles. But they are not something alternative practitioners tend to like. Why? Because, using these strict definitions, many alternative therapies are neither of proven efficacy nor effectiveness.
What can be done about this unfortunate situation?
Simple! Let’s re-formulate the definitions of efficacy and effectiveness!
Efficacy, according to some alternative medicine proponents, refers to the therapeutic effects of the therapy per se, in other words, its specific effects. (That coincides almost with the scientific definition of this term – except, of course, it fails to tell us anything about the boundary conditions [optimal or real-life conditions].)
Effectiveness, according to the advocates of alternative therapies, refers to its specific effects plus its non-specific effects. Some researchers have even introduced the term ‘real-life effectiveness’ for this.
This is why, the authors of the study discussed in my previous post, could conclude that “aromatherapy massage and reflexology are simple… effective… interventions… to help manage pain and fatigue in patients with rheumatoid arthritis.” Based on their data, neither aromatherapy nor reflexology has been shown to be effective. They might appear to be effective because patients expected to get better, or patients in the no-treatment control group felt worse for not getting the extra care. Based on studies of this nature, giving patients £10 or a box of chocolate might also turn out to be “simple… effective… interventions… to help manage pain and fatigue in patients with rheumatoid arthritis.” Based on these definitions of efficacy and effectiveness, there are hardly any limits to bogus claims for any old quackery.
Such obfuscation suits proponents of alternative therapies fine because, using such definitions, virtually every treatment anyone might ever think of can be shown to be effective! Wishful thinking, it seems, can fulfil almost any dream, it can even turn the truth upside down.
Or can anyone name an alternative treatment that cannot even generate a placebo response when administered with empathy, sympathy and care? Compared to doing nothing, virtually every ineffective therapy might generate outcomes that make the treatment look effective. Even the anticipation of an effect alone might do the trick. How often have you had a tooth-ache, went to the dentist, and discovered sitting in the waiting room that the pain had gone? Does that mean that sitting in a waiting room is an effective treatment for dental pain?
In fact, some enthusiasts of alternative medicine could soon begin to argue that, with their new definition of ‘effectiveness’, we no longer need controlled clinical trials at all, if we want to demonstrate how effective alternative therapies truly are. We can just do observational studies without a control group, note that lots of patients get better, and ‘Bob is your uncle’!!! This is much faster, saves money, time and effort, and has the undeniable advantage of never generating a negative result.
To most outsiders, all this might seem a bit like splitting hair. However, I fear that it is far from that. In fact, it turns out to be a fairly fundamental issue in almost any discussion about the value or otherwise of alternative medicine. And, I think, it is also a matter of principle that reaches far beyond alternative medicine: if we allow various interest groups, lobbyists, sects, cults etc. to use their own definitions of fundamentally important terms, any dialogue, understanding or progress becomes almost impossible.