| The RCT and Homeopathy: Randomization
Randomization is a simple procedure that distributes trial participants
between control and experimental groups, as suggested by the name,
on a random basis. In this way, any factors that tend toward a particular
response to treatment are excluded from influencing the frequency
of that response in either of the groups. In the event there is
still concern that one group or the other is, on the whole, more
responsive or more resistant to the treatment under investigation,
the trial may be split in two, so that the sides are switched, and
in the second half of the trial the experimental group becomes the
control group, and vice versa. This ‘crossover’ technique
effectively controls for vulnerability of the RCT to inequalities
between the groups, at least in a trial of conventional treatments.
But in the homeopathic trial, in the circumstances discussed above,
the crossover simply won’t work. This is clearly the case,
since, as we discussed, some effects in enhancing placebo response
effect only the placebo group. Thus, in a crossover, although
the populations of the control and experimental groups are exchanged,
the effects of the trial situation on outcomes remains
the same – the effects are specific to the nature
of the “control” itself, not to the characteristics
of the participants who populate it.
A Second Layer of Observation – Selecting and Interpreting
Outcomes
Simply, numbers do not speak for themselves. Two examples will
provide a sample of problems that may be encountered designing a
trial, and interpreting its outcomes, in the absence of reasonable
clinical (i.e., not statistical) guidelines.
In a recent article,2 Brien et. al. use a list of symptoms as
the basis for evaluating response to the homeopathic remedy. On
this list, 5 symptoms were real symptoms found in the proving record
for the test remedy; the other 5 symptoms were not proving symptoms
of that remedy: thus, if a participant reported he had experienced
one of the latter 5 symptoms, it was clear his response was a placebo
response, rather than a response to the remedy. In measuring outcomes,
however, the authors established a procedure in which verum symptoms
were not counted if that same participant produced two
symptoms from the second group. Though they did not clarify the
point, it is clear they assumed that since that participant showed
a fairly marked suggestibility, in producing two placebo responses,
it was safe to assume that the supposed verum response was itself
merely a result of suggestibility.
The problems with such an approach seem fairly obvious: without
any knowledge whatsoever of how symptoms form in response to homeopathic
remedies, nor even any “objective” proof that the remedies
do or do not provoke such symptomatic responses, these authors introduced
a completely arbitrary definition that resulted in a reduction in
the “efficacy” of the homeopathic remedy, as reflected
statistically through the blinded trial. This frankly incredible
presumption reflects, furthermore, the inability of the
randomized, blinded trial to understand trial outcomes,
in short, to do anything more than count them. In the present case,
the RCT reduced verum response – equally, to be sure (statistically)
– in both the experimental and the control group, but obviously
could not determine whether the verum symptom was a response to
the real medicine, or to the sugar pill, in the case of the verum
prover.
In other words, reduction of count for a participant in the control
group is unobjectionable: there is no way that the apparent verum
symptom could have been a response to the real medicine, because
the participant did not receive the real medicine. But, reduction
of count for a participant in the experimental group does nothing
less than strike evidence of efficacy from the record!
All of us – patients, trial participants, authors,
and statisticians – will respond to some medications, and
not respond as much or as well to others, and will also respond
to placebo. The presence of a placebo response in a participant
in the verum group, in short, has no bearing on whether an accompanying
verum response is truly a response to verum, as opposed to a placebo
response that coincidentally mimics a verum response.
Brien et. al. also note that “…consumption [by trial
participants] of alcohol and possible undisclosed recreational drug
intake may minimize any homeopathic response. Lifestyle factors
may colour the outcome, e.g., Belladonna-related symptoms of ‘headache’
and ‘sinking and rising sensation in his head’ were
reported following high alcohol intake for the previous evening.”
Yet, in their conclusions, the authors ignore their own caveats,
citing the statistically negative outcome of the trial, for homeopathy,
and recommending “…future research should focus on …
those factors such as the therapeutic relationship and the process
of the homeopathic consultation that may mediate the apparent success
of the homeopathic process.”
Clearly, these authors demonstrate the point, that conclusions
drawn from the statistical outcomes of the trial need not accurately
reflect the significance of those numbers.
Discussion: Implications for Research
In the present paper, four situations have been discussed, that
impact our ability to review results of objective research, with
confidence that findings accurately reflect events in the real world.
Normally, such research is, of course, subject to review for determining
whether findings are statistically reliable. As a simple example,
one might consider whether the sample size was sufficient to permit
a confident statistical outcome, since too small a sample will be
vulnerable to wild fluctuations in trial results: in the event a
medical trial had, for example, five participants, 3 of whom showed
‘positive’ for a medicinal effect, that would reflect
a 60% success rate for the medication. Yet a swing of one case,
from positive to negative response, would alter the outcome to reflect
a 60% failure rate for the medicine in question.
The present review of randomized trials, however, suggests that
observational assessment of the trial design and outcomes
– a kind of “clinical” evaluation of the experiment
– is needed to ensure the logical, or “experiential”
aspect of the trial does not introduce confounders of its own. We
have, as stated, already identified four such potential confounders:
1) The first problem was actually identified in an article published
last April,1 as previously referenced. In that situation,
we reviewed the way in which antidoting substances could produce
symptoms in participants in the control group, while antidoting,
or eliminating symptoms in the verum group. The net effect of
this differential action within a trial of homeopathic medicine,
was to introduce a statistical advantage for placebo. This was
the first time even a hint of bias, in the internal workings of
a randomized trial, had been observed in the research literature.
As I have discussed before, it seems most likely that the impact
of this confounder, on trial outcomes, would in most cases be
quite small.
2) The second problem, identified in the present article, is
reflected in the protocol design that establishes a list of symptoms,
against which frequency of verum v placebo response is to be gauged.
As we saw, the limitations on symptoms considered, results in
the unintended effect that verum group draws from an impoverished
range of allowable symptomatic responses, while, by definition,
the selected symptom list established the full range
of expectable responses for the placebo
group. As discussed, this leads to a statistical advantage for
placebo, within the so-called objective framework of the randomized,
double blind study, a research design engineered to protect against
observer bias, but clearly subject to potentially significant
systematic bias, introduced by faulty trial design.
Compared to the first problem, this issue may potentially have
a very dramatic impact: in the trial reviewed here, the symptom
list that verum participants drew from was reduced from 1440 symptoms
(identified for Belladonna
by Hahnemann, in the Materia
Medica Pura), to just 5 symptoms permitted by the protocol.
3) The third confounder, interfering with objectivity of outcomes
in the RCT, is found in a process in which verum and control groups
were both scored for production of real proving symptoms for the
remedy being studied: thus, a positive response for a participant
in the control group reflected a “point” for placebo.
What is interesting in this study, is that the authors decided
to discount verum symptoms from all participant responses
– control and verum groups – if the responder
also produced two symptoms that were not real
proving symptoms as established in the materia medica. In short,
verum symptoms produced by responders in the verum group were
not counted, on the assumption that accompanying placebo
responses suggested that the responder was so highly suggestible
as to justify discounting even a potentially legitimate verum
response!
Note: the purpose of this study was ostensibly to determine
whether homeopathic remedies have any real effects, yet the authors
concluded, in advance of the trial, that placebo responses would
be given evidentiary weight in evaluating verum responses!
In all likelihood, it appears that this confounder would, like
our first example, have a real, but minimal impact on the eventual
statistical results.
4) Finally, we reviewed a paper reporting outcomes of a homeopathic
proving trial, in which the authors noted factors that could likely
have some impact on the experimental outcomes. Nevertheless, in
their concluding comments, they ignored these factors, choosing
instead to recommend that future research in homeopathy focus
on mechanisms such as placebo response, to account for the appearance
of success in real world practices. But it would seem, that a
review of the effect of antidotes would be a more legitimate recommendation,
based on these authors’ own observations.
In short, this example documents the way in which interpretation
of data by the authors can effectively contradict a more objective
record of experimental outcomes.
In summary, these examples illustrate a variety of ways in which
the objectivity of the randomized, blinded trial may be compromised.
The first three situations are peculiar to the situation of the
homeopathic proving trial, or treatment trial. These paradoxical
results are made possible by the fact that homeopathic remedies
produce symptoms rather than just eliminate them, as with
conventional medications. These results are also encouraged because,
in context of the large numbers of symptomatic responses associated
with homeopathic remedies, it becomes cumbersome and perhaps altogether
impractical (financially or logistically) to implement a thoroughgoing
symptom harvest. In an efficacy trial of conventional medications,
on the other hand, the focus of the action of medicine is narrowly
circumscribed, therefore easier and more practical to observe.
The decisions of the research team, to discount verum symptoms
in case 3, above, and to disregard acknowledged confounders in case
4, represent, on the other hand, a type of bias introduced into
research proceedings through the medium of human error – poor
definition of terms, failure to address all aspects of the research
situation in their summary. In short, these interpretative errors
can have an effect on trials in homeopathic research as well as
in trials of conventional medication.
What seems perfectly clear, is that future research efforts should
be directed to evaluating the efficacy of randomized and blinded
research trial itself, and should seek to identify as many
situations as possible in order to measure the impact of therapeutic
dynamics (e.g., the homeopathic mechanisms of action) and logical
errors of the research team, on the accuracy – the credibility
– of statistical and analytical results of published trials.
It is not accidental, nor unimportant, that our intuitive grasp
of the situation agrees with the outcome of the conventional trial:
we see that aspirin works, and the trial demonstrates that this
is true – perception is vindicated. It is frankly beyond dispute,
that we should be able to expect the same agreement as between perception
and experimental outcomes, in the case of the homeopathic trial,
or, failing this, we have a right to expect a responsible examination
of the sources of disparity. I believe the present paper represents
an important step in that direction.
Conclusion
The RCT has been involved as a major player in scientific research
in recent decades. There certainly can be no justification in questioning
the profound power of this research technology for controlling bias,
in the effort to produce objective, and, more important, reliable,
or credible, observational data. But, in case the skeptics in our
midst haven’t noticed, the concept of the RCT, as an idealized
instrument capable of easily measuring clinical process in homeopathy,
has just been falsified.
This does not mean that the RCT can not be used to measure
homeopathic action; indeed, at present, it is simply too early to
tell, how significant the errors will be, that are introduced into
the blinded statistical study by the transactions between blinding,
placebo control, and those characteristics of homeopathic practice
that distinguish it from conventional medicine. This is the first
time, after all, that such paradoxical results have been shown in
the workings of the double blinded trial. There is more to be done,
to satisfy ourselves that the now dented instrument of the RCT can
be relied on in all of the applications to which its faithful wish
to put it, but we are not yet at the point, either, of concluding
that more careful and more skillful design of trial protocols can’t
overcome the obstacles in the path of reliable – credible
– research.
In short, to value something highly, even to hold it very dear,
is not to cherish it as an icon. It does not do to wave your magic
wand, and chant three times, slowly, “Randomized! Double Blind!
Placebo Controlled! Trial!! Randomized! Double Blind…!!”
It does not generate confidence that the outcome of a trial can
be trusted, just because its numbers add up; one can give a calculator
to a child, but all one accomplishes by that, is to limit what one
can expect from the calculator.
One quality the child lacks is perspective. Another is
experience. These are keystones of knowledge and understanding.
To the child, however, they don’t matter, as all he is concerned
about are his numbers. But in science, we need to know if the numbers
apply to real objects, and real processes, in the real world. As
I believe I have clearly demonstrated – far beyond, frankly,
what I expected to be able to do when I began – current practice
in statistical research is as self-absorbed as a child, preoccupied
with discovery of its own unfolding powers, but not yet at a stage
of maturity as to grasp its relations to external reality.
I have to frankly laugh, though it be rude, at the thought that
adherents of this methodology, in applying it to research into homeopathy,
have managed to find not one, but at least four mechanisms (that
I have identified) by which production of placebo response is enhanced
in the Randomized Trial! Truly, it is a wonder that homeopathy does
even as well as placebo in these trials, let alone outperform
it!
Perhaps it all has something to do with the fact that so many
researchers, as it appears, prefer to think of themselves as skeptics,
rather than scientists, and to busy themselves more with doubt than
with curiosity. And certainly, it has to do with the fact, that
these self-same skeptics eschew the specialized knowledge of professionals
in the fields they pretend to investigate. “Nonsense!”
one can almost hear them saying. “If there were radio sources
in deep space, surely even a poorly designed optical telescope would
have found some piece of evidence for it by now!”
But perhaps one day, when someone combines understanding with
calculation, and reason with randomization, the truth will finally
be revealed. To be fair, it should be commented that statistical
research, after all, is still a very young branch of science, and
that there are, for good reason, no names amongst its practitioners
that have been elevated to the pantheon, as Hahnemann to homeopathy,
Freud, Jung, Adler, or Pavlov to psychology, Darwin or Mendel to
biology, Einstein or Bohr to physics. This reflects, frankly, that
there has as yet been no one to grasp the broader sweep and implications
of statistical methodology in its various applications. It is after
all the merest blink of an eye since it was realized, in the wake
of the thalidomide scandal, that second generation testing should
be a standard practice in such trials. Further, the ‘profession’
of statistical research hasn’t even been successful in helping
its audience understand that ‘efficacy’ is unrelated
to ‘safety,’ and that the RCT has nothing to
say about the latter.
Simply put, this is still a youthful science, a useful and promising
one, to be sure, but immature, and even naive, zealous, and self-satisfied,
in the way of the young. One only hopes that, as they continue to
stump for repression of medical practices they don’t like,
for whatever personal motives they may have, these supposed skeptics
will at least report honestly to the public and to government leaders,
that their claim to perfect objectivity has been slain.
References
1 Shere, Neil D. 2005. Proving
Homeopathy:, hpathy ezine (April),
2 Brien, et. al. 2003. Ultramolecular homeopathy has no observable
clinical effects. A randomized, double-blind, placebo-controlled
proving trial of Belladonna 30C.” British Journal of
Clinical Pharmacology, 56:562-568.
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