There probably is no area in health care that produces more surveys than alternative medicine. I estimate that about 500 surveys are published every year; this amounts to about two every working day which is substantially more than the number of clinical trials in this field.
I have long been critical of this ‘survey-mania’. The reason is simple: most of these articles are of such poor quality that they tell us nothing of value.
The vast majority of these surveys attempts to evaluate the prevalence of use of alternative medicine, and it is this type of investigation that I intend to discuss here.
For a typical prevalence survey, a team of enthusiastic researchers might put together a few questions and design a questionnaire to find out what percentage of a group of individuals have tried alternative medicine in the past. Subsequently, the investigators might get one or two hundred responses. They then calculate simple descriptive statistics and demonstrate that xy% (let’s assume it is 45%) use alternative medicine. This finding eventually gets published in one of the many alternative medicine journals, and everyone is happy – well, almost everybody.
How can I be such a spoil-sport and claim that this result tells us nothing of value? At the very minimum, some might argue, it shows that enthusiasts of alternative medicine are interested in and capable of conducting research. I beg to differ: this is not research, it is pseudo-research which ignores most of the principles of survey-design.
The typical alternative medicine prevalence survey has none of the features that would render it a scientific investigation:
1) It lacks an accepted definition of what is being surveyed. There is no generally accepted definition of alternative medicine, and even if the researchers address specific therapies, they run into huge problems. Take prayer, for instance – some see this as alternative medicine, while others would, of course, argue that it is a religious pursuit. Or take herbal medicine – many consumers confuse it with homeopathy, some might think that drinking tea is herbal medicine, while others would probably disagree.
2) The questionnaires used for such surveys are almost never validated. Essentially, this means that we cannot be sure they evaluate what we think they evaluate. We all know that the way we formulate a question can determine the answer. There are many potential sources of bias here, and they are rarely taken into consideration.
3) Enthusiastic researchers of alternative medicine usually use a small convenience sample of participants for their surveys. This means they ask a few people who happen to be around to fill their questionnaire. As a consequence, there is no way the survey is representative of the population in question.
4) The typical survey has a low response rate; sometimes the response rate is not even provided or remains unknown even to the investigators. This means we do not know how the majority of patients/consumers who received but did not fill the questionnaire would have answered. Often there is good reason to suspect that those who have a certain attitude did respond, while those with a different opinion did not. This self-selection process is likely to produce misleading findings.
And why I am so sure about all of theses limitations? To my embarrassment, I know about them not least because I have made most these mistakes myself at some time in my career. You might also ask why this is important: what’s the harm in publishing a few flimsy surveys?
In my view, these investigations are regrettably counter-productive because:
they tend to grossly over-estimate the popularity of alternative medicine,
they distract money, manpower and attention from the truly important research questions in this field,
they give a false impression of a buoyant research activity,
and their results are constantly misused.
The last point is probably the most important one. The argument that is all too often spun around such survey data goes roughly as follows: a large percentage of the population uses alternative medicine; people pay out of their own pocket for these treatments; they are satisfied with them (if not, they would not pay for them). BUT THIS IS GROSSLY UNFAIR! Why should only those individuals who are rich enough to afford alternative medicine benefit from it? ALTERNATIVE MEDICINE SHOULD BE MADE AVAILABLE FOR ALL.
I rest my case.