Evidence of the effectiveness of homeopathy
Michel Van Wassenhoven
Abstract
The present paper discusses possible approaches to the studies on the effectiveness of Homeopathy. These include classic evidence – clinical and basic research – and internal evidence, proper to Homeopathy as a singular medical system, which include the pathogenetic and the clinical verification of homeopathic symptoms. Concerning the latter, a new approach, grounded on Bayesian statistics is presented. All the criteria employed show the clinical effectiveness of Homeopathy.
Keywords: Homeopathy; Effectiveness; Evidence
Classical evidence
Clinical evidence
An experimental design is only relevant if it approaches the observed phenomenon in its specific structure and if the study subject may be isolated from all external influences. In human medicine, although the effects of medicines are specific, a number of factors, including the psychological, are related to unspecifiable effects. For this reason, studies in veterinary medicine are significant in homeopathy, as it is easier to isolate the effects of treatments, the placebo effect can be dismissed and ethical concerns are fewer. Such studies include a rather homogeneous samples of a large number of animals. Nevertheless, a well designed study has to take the particularities of homeopathic research into account, such as the law of similars and idiosyncratic symptoms.
In Europe, the homeopathic treatment is allowed in herd-breeding farms, and its use allows to avoid chemical residues in the foodchain. In recent studies, the use of complex homeopathic remedies was assayed in double-blind models, with homogenous samples, a satisfactory number of animals and easy-to-apply protocols in the farm setting.1
Concerning human clinics, a recent analysis of the literature (2000-2006), including the application of validated quality of life questionnaires, 19,292 (70%) of the patients referred significant clinical improvement.2 The use of homeopathic remedies decreased the cost of therapy and non-working days, when compared to the conventional treatment.2
The homeopathic treatment elicited better results than the conventional is asthma, palliative treatment of cancer patients, childhood hyperactive syndrome and upper airways infections, with a lesser index of side-effects.2
To confirm this trend, we conducted a literature research, searching for evidence of the effectiveness of the homeopathic treatment in a wide scope of specific medical conditions. This research was performed on 4 data-bases: Medline, Cochrane Libraru, Hominform and Ciscom (Research Council for Complementary Medicine data-base), searcing for statistical evidence favorable to homeopathy in published studies where a comparison to placebo or other kinds of medication was employed.
The results are shown in Table 1.
However, it mus be noticed that in this research, the ground was diagnosis/prescription performed according to conventional medicine criteria, while homeopathy extends its field beyond specific and singular medical conditions. Second, this researched aimed exclusively to studies including at least one experimental report showing the positive effect of homeopathy. That is to say, it was not sought to mask inconclusive or negative studies, but the aim was to highlight medical conditions where the effectiveness of homeopathy was objectively proved.
Basic research
A number of health-care professionals are still discomfortable with homeopathy because they do not understand the mode of action of
its remedies. More than 800 papers have been published on this subject, on cell-cultures, vegetal and animal models.3 Physical science has also shown an interest, and through nuclear magnetic ressonance and termoluminiscence it was possible to detect a specific signal of the original substance in homeopathic solutions well above the number of Avogadro.3
These are well conducted studies, in controlled conditions, satisfactory number of individuals in the samples and statistic treatment. Facts are indisputable, statistically significant and reproductible, even though they cannot be explained.
Internal evidence
Homeopathy is a singular medical system, grounded on the law of similars. That is to say, a homeopathic remedy heals in the sick individual symptoms similar to those it elicits when tested in a healthy organism (proving or pathogenesy). For this reason, in both classic clinical studies and basic research, the law of similars has to be taken into account in order to verify significant effectiveness.
Provings
The homeopathic remedies derive from an experimental procedure founded by Hahnemann and which has been continuously employed for more than 2 centuries. A remedy is taken by a healthy volunteer until it begins to elicit symptoms. These symptoms are carefully recorded.
The quality of each symptom is more important than the number of provers and the number of symptoms obtained. Currently, this experimental procedure is carefully codified4 and systematically performed with a placebo control. When a coherent list of symptoms was obtained (image of the remedy) it is published, but it only becomes significant when such symptoms are confirmed in further provings.
A proving may be compared to the qualitative phase I of experimentation.
Such a study is necessary in the process of approval of new drugs.5 In homeopathy, thousands of different remedies are used daily, and for each, hundreds of detailed symptoms are listed.
It can be established a level of evidence for each remedy in the homeopathic materia medica. When this level is high, the possibility that the remedy will heal the same symptoms in the sick individual will be equally high. When more than one symptom are meaningful in the patient in the same materia medica of the remedy, more complete and remarkable will be the process of healing.
A possible way is the review of published literature. A first encompassing study of the provings published in the United Kingdom between 1945 and 1955 was published in 1998,6 a more recent, and encompassing, one has been recently published.7 Certainly, more and better provings must be performed, as well as critical reviews.
Clinical verification of homeopathic symptoms
Hering established the 5 steps needed to obtain a characteristic symptom; clinical verification is the fifth:8
1 - The possibility for a substance to elicit some symptoms, which, at times, may even be toxic.
2 - The probability of this same substance, when dynamized, to elicit several symptoms in healthy provers.
3 - Confirmation is obtained when this same dynamized substance, prescribed to healthy provers, confirms some of the symptoms obtained in previous provings.
4 - Corroboration, i.e. the analysis of the place of the probable symptom and its constitution through the available physiological and pathological notions.
5 - The clinical verification is effected in the actual treatment of patients, through the correspondence of the probable, confirmed and corroborated symptoms to the clinical outcome.
Thus, traditional verification consists in: 1) collection of clinical data; 2) selection of a remedy; 3) selection of indisputable cases; 4) guiding symptoms; 5) verification; 6) adequation of degrees in the repertory. It is traditionally grounded on the clinical experience of eminent homeopaths.
The sensitive point in this model is the selection of the cases, which must be indisputable, i.e. “absolute failures” or “spectacular cures” after the intake of the remedy. The personal experience of the author, of 25 years of homeopathic practice, allows to propose a guide for outcome evaluation. (Table 2) Outcomes are compared to the symptoms of the patient which were selected for the choice of the remedy.
Outcomes confirm or invalidate the link between the experimental symptoms and the symptoms presented by the patient. With the use of new statistical tools, clinical verification may be improved. Bayesian statistics is admitted in medicine for the evaluation of processes hard to evaluation through double-blind models. For example, the prognostic value of medical scanning techniques, emergency-care remedies. The ratio of positive and/or negative probability between an action and its final outcome can be assessed.
In homeopathy, the relationship between one (or more) symptom(s) of the patient and the effectiveness of the prescribed remedy might be objectively predicted on the grounds of the clinical outcome of the same treatment, previously applied, and the prevalence of such symptoms in the population. The collection of clinical data in a systematic way, facilitated by the currently regular use of computers by homeopaths, is a new research approach that will allow to produce such predictive values.
In this case, differently from the traditional analysis, all data in a clinical data-base are employed. Bayes’ mathematical analysis is performed. The degree of truly positive cases is divided by the degree of false-positive cases (likelihood ratio, LR). This method can be applied prospectively or retrospectively.
The retrospective study is grounded of the collection of data in everyday practice. The positive probability ratio (LR+) indicates that a remedy will be effective if the symptom is present, and the higher it is, the better. LR- indicates that the remedy will not be effective if the remedy does not have the symptom, and the less it will be, the more LR- approaches zero. (Figure 1) LR must be defined in prospective studies, taking the prevalence of a symptom in the general population into account. Currently, a study is being conducted by the Dutch group of the Vereniging van de Homeopathische Artsen van Nederland (VHAN).
Conclusions
Looking to the results already obtained and verify, we can affirm that the homeopathic method has a right to be employed in 21st century medicine. Complementary research is, certainly, welcomed and needed, but the worth of homeopathy cannot continue to be denied. Veterinary studies show the clinical effectiveness of homeopathy.
Human research reveals important clinical improvement in 70% of patients. In certain specific pathological conditions, the effectiveness of homeopathy obtained a high ratio of statistical significativeness. The present state of basic research allows to conclude that ultradilutions possess biological activity.
Modern medicine employs new statistical approaches to observe the effects of treatments in everyday practice; these technique are particularly well suited to the evaluation of homeopathy.
Within internal evidence, clinical verification is a necessary step to validate the homeopathic therapeutic method. In this regard, it has to be taken into account that the validation of outcomes depends on the amount of available data and that the collection of clinical data must be increased.