The Practitioner’s Need-To-Know Overview of Homeopathic Research

Iris R. Bell, MD PhD MD(H)

Introduction

As are practitioners in most other areas of health care, homeopaths in clinical practice are often too busy with patient care to keep up with much of the research literature in their field. Furthermore, even in conventional medicine, clinicians often point out that they find research papers irrelevant to their everyday work with patients. Even large-scale clinical trials of drugs that they prescribe daily seem not to provide much useful information about what to do for a specific patient. Homeopaths already know this, as their field is already so intensively focused on individualized care involving both the non-specifics of the patient-provider relationship and specifics of the individualized remedy (T. D. Thompson & Weiss, 2006), and patients respond with complex multidimensional changes (Bell, Koithan, Gorman, & Baldwin, 2003; M. Oberbaum, Singer SR, Vithoulkas G., 2005).

Life – also known as “extenuating circumstances” - seems to make the seemingly ideal treatment not quite right for a given person – because of side effects, interactions with drugs, complications from comorbid conditions not allowed in the original clinical trials, high cost, poor access, reduced willingness or ability to take the treatment on the recommended schedule, cultural, family, or personal beliefs against the treatment, and so on. Overall, real-world clinical practice is usually vastly different from what medical researchers spend most of their time studying (Freeman & Sweeney, 2001).

To add even more confusion to the situation, even in conventional medicine, the results of large scale real-world observational trials and the results of controlled, double-blind clinical trials can lead to opposite conclusions. For example, hormone replacement therapy (HRT) was touted as a way to reduce menopausal symptoms and various health care risks for women – until new data raised serious concerns that HRT actually increases those same risks.

Homeopaths encounter similar dilemmas with treatments such as Arnica. That is, clinical experience tells them the remedy is helpful in many first aid situations, but the research literature shows mixed results (for many reasons, especially involving study design), with many negative studies showing Arnica of no benefit (Ernst & Pittler, 1998; W. Jonas, Lin, Y., Williams, A., Tortella, F., Tuma, R., 1999; Oberbaum et al., 2005; Ramelet, Buchheim, Lorenz, & Imfeld, 2000; Stevinson, Devaraj, Fountain-Barber, Hawkins, & Ernst, 2003). When clinicians have the opportunity to look at the details of each study, they usually can point out glaring problems with a mismatch between clinical practice and the actual study design – in terms of choice of clinical condition, remedy, and dosing schedule. Data suggest that Arnica may be useful in certain bruising conditions (e.g., facial plastic surgery), but not necessarily all type of surgical procedures (e.g., carpal tunnel repair) or sports injuries.

When the data contradict personal experience, many practitioners and patients choose to act on the side of their own experience with a treatment – in both conventional and alternative health care. Skeptics just use such behavior as further “proof” that proponents of homeopathy are irrational and unscientific.

However, it is possible to be rational and scientific – and find logical ways to evaluate articles with findings that do - or do not - coincide with strongly-held beliefs, to make sense of conflicting information. Often methodological design or analysis problems contribute to the divergence between clinical impressions and randomized clinical trial findings. The appropriate response is to revise study design to better reflect clinical practice, not to ignore or attack results globally that are counter to expectation.

Reasons for Homeopathic Research

So, why bother with research at all (Bell, 2003)? There are two major pragmatic reasons for paying attention to research in homeopathy:

            (1) Developing the Evidence Base on Homeopathy (aka Survival of the Field) – Western drug-oriented medicine still holds immense political, legal, and financial power in the health care arena. People in power do not always understand or care about alternative medicine practices; sometimes they see these practices as risky for patients in terms of physical safety or “unnecessary” expenses. They can find ways to squeeze practitioners out of practice by legal actions against providers and financial actions (restricting practice and payment).

Establishing homeopathy as an evidence-based health care system is one essential element in a viable offense and defense against such attacks. Homeopaths who need to give talks on homeopathy in their local communities or to defend their own practice when skeptics come calling will find this type of information vital.

Types of research that fall into this broad category include placebo-controlled randomized clinical trials, large scale observational outcomes studies, and cost-effectiveness studies.

            (2) Improving Clinical Care for Patients – Even purists in any field agree that the ideal stated in the textbooks and the reality in practice can differ. Any practitioner who is honest about their field and their own practice will acknowledge that there is always room for improvement. Research can provide ways to know where to begin in this process.

Here, we can ask questions like:

“Are combination remedies and individual remedies comparable or different in clinical effectiveness for treating certain acute illnesses?”

“When do patients benefit from LM dosing versus C potency dosing?”

“What is the ‘right’ potency to use in a given patient?”

“Does zigzagging to cure through a series of remedies have the same benefits and downsides for a patient as does finding a single remedy that covers the whole case early on?”

“What individual differences between people make them better or worse responders to homeopathic treatment?”

“How do the clinical outcomes of people treated with homeopathy versus allopathic drugs differ for a specific clinical picture?”

“Which allopathic drugs interfere with homeopathic treatment – and in what ways?” 

“What factors do antidote remedies and under what circumstances – and which patients?”

“Under what circumstances does one system of finding the remedy work better than another?”

“Are there cultural and/or biological differences between patient populations that impact applying the teachings of various master homeopaths from different countries in your own home town?”

“How can we improve the reliability and clinical applicability of provings so that we obtain good remedy pictures on which to base prescriptions?”

These and many more questions relate to improving care for patients at a practical level. Homeopaths should want to know answers to these types of questions in order to make changes in their practice and improve patient outcomes. There are many opinions on most areas of homeopathic practice – research findings can help inform the decisions that each practitioner ultimately has to make for each patient.

The bibliography resources below provide some starting points for addressing these two main reasons why practitioners might want to learn more about the research literature. Just as any good homeopath keeps up with new case reports in clinical journals, at conferences, and on the internet and becomes familiar with new ideas about practice, the research literature can make us think even harder about cases in ways we currently might not do – all for the advancement of the field and better outcomes for patients.

Incorporating homeopathic research helps reduce our uncertainty, add professionalism to the way we present homeopathy in our communities, and identify the important questions that need answers (beyond opinions). Ultimately, this effort will help homeopathy to strengthen and grow as a health care discipline.

(1) Developing the Evidence Base on Homeopathy Papers

Allopathic Conditions in which Homeopathy has been studied

Most studies have been on small samples and receive criticism for various methodological shortcomings including sample size per se. Nonetheless, these papers may provide some guidance to practicing homeopaths on how to approach treatment of individual patients with similar allopathic diagnoses.

“Lumping” Approaches to Research

Allopathic Gold Standards – Meta-Analyses and Systematic Reviews

Take-Home Points:

Meta-analyses are a formalized type of systematic review in which the results of different, multiple randomized controlled trials are systematically assessed and rated numerically for allopathic study quality, then combined to draw general conclusions about a particular treatment in a specific allopathic condition.

Notably, the highest profile meta-analyses (Linde et al 1997 and Shang et al 2005) combined trials of homeopathically-prepared remedies prescribed homeopathically, isopathically, and allopathically across multiple allopathic conditions. They do not and cannot address the efficacy of usual care homeopathy by any one practice approach (classical, complex, clinical, isopathic) in any single allopathic condition or for any single homeopathic remedy. The analogy would be for someone to take all of the best clinical trials done on all types of allopathic drugs to run one big meta-analysis in order to ask the question – “Does allopathic medicine work?”

Even without elegant statistics, obviously the answer for allopathic medicine is – sometimes, under certain experimental conditions, allopathic medicine produces certain good outcomes, certain bad outcomes, and sometimes no change at all. It also depends how you define a “good” or “bad” outcome. From a homeopathic perspective, a suppressive effect would be a bad outcome, but allopathic rating systems would consider a suppressive outcome as “good.”  At present, it is probably fair to draw the same kind of conclusion about “homeopathy” from existing metaanalyses, i.e., that it produces certain good outcomes, certain bad outcomes (though fewer than with allopathic medicine, based on available data), and sometimes no change at all.

In conventional medicine, the meta-analysis would be restricted to a specific medication or surgical procedure for a specific diagnosis. At best, some of the earlier meta-analyses examined isopathically-prescribed allergens in rhinitis patients. Other methodological problems with the actual statistical procedures are also a major issue with accepting the validity of most meta-analyses on homeopathy as a whole field.

Another important point to make about these meta-analyses is that the quality ratings for studies derive from standards relevant to studies of allopathic drugs. Quality ratings for reporting studies in homeopathy to date have never established or included any standards for quality of the homeopathy given (including experience of practitioner(s), prescribing method, confidence of practitioner in remedy prescription, ability to change remedy choices for non-response, management such as use of LM potencies or dose repetition to deal with possible antidoting effects of concomitant allopathic drugs, etc), study duration adequate to expect change in the allopathic condition, and so on (Dean, Coulter, Fisher, Jobst, & Walach, 2006).

Finally, one systematic review found that conventional medical journals show a bias toward publishing negative studies about homeopathy, whereas CAM journals show a bias toward publishing positive studies. However, for meta-analyses, to date, the bias is more evenly distributed between positive and negative studies in mainstream medical and complementary medical journals (Caulfield, 2005).

Observational Outcome Studies

Observational studies can vary in quality, from case-control and cohort designs to simple chart reviews or audits of case series. Skeptics will often object to observational data, saying that it is not as “good” as the controlled studies – but the evidence does not support this claim. In fact, well-designed observational studies using comparison groups (to compare treated patients with those receiving standard care or no care, thereby controlling for the natural course of the disease) generate findings of at least equivalent capacity to detect significant treatment effects (J. Concato, 2004; J. Concato, Horwitz, R.I., 2004; Concato, Shah, & Horwitz, 2000).

Observational studies are particularly valuable for homeopathy research because of a) the relative lack of academically-based researchers and major research funding worldwide; b) the relevance of real-world context, including complex and multiple diagnoses/symptoms, and longer-term periods of evaluation for assessing homeopathic outcomes; and c) theory-driven models for mediators of change in homeopathy (Milgrom, 2006b). Observational studies rely on case data from real patients in real practice settings and can involve large numbers of patients treated for short- or long-term periods. This permits determination of outcomes that may be much more relevant to clinical practice than most controlled clinical trials (with typically durations of 12-16 weeks) or meta-analyses that depend on randomized controlled trials.

Of note, observational studies on homeopathy have reported consistently highly favorable outcomes, typically at rates of 70-80% improvement, along with high levels of patient satisfaction and low rates of adverse effects. Obviously, especially in studies without comparison groups, skeptics could point to potential bias of the authors in favor of homeopathy to discount such findings. However, one recent observational study did include a control group (see Witt et al 2005). Studies on cost of homeopathic care vs allopathic care also have suggested that, depending on the fiscal structure of the health care system in which the homeopathy is given, the overall costs either decrease or are equivalent (Frenkel & Hermoni, 2002; van Wassenhoven & Ives, 2004; C. Witt, Keil T, Selim D, Roll S, Vance W, Wegscheider K, Willich SN., 2005).

In complementary medicine generally, studies of safety and cost in the face of equivalent or better outcomes to conventional care may be even more useful in making the case for using and insurance reimbursements for alternative therapies, including homeopathy (Bornhoft, 2006; Maxion-Bergemann, Wolf, Bornhoft, Matthiessen, & Wolf, 2006). Reports of safety (adverse reactions) with homeopathy are generally low in most controlled trials, although one clinical audit study suggested that homeopathic “aggravations” are fairly common (approximately ¼ of patients) (E. Thompson, Barron, & Spence, 2004). We need much more research of this type to make the case at this point in time.

Basic Science Papers on the Nature of Remedies

The single most important argument that skeptics of homeopathy raise is that the remedies, at least those potencies above 24x or 12c, are diluted so much that there are no more physical molecules of the original source substance remaining (diluted past Avogadro’s number of 6 x 10²³) (Mastrangelo, 2006). Being prepared to cite some of the papers mentioned below and provide references is critical for homeopaths who encounter skepticism from patients, family members, and allopathic physicians.

The research is showing that it is the succussion process that is essential for generating persistent changes in solvent, even when remedy source material molecules are no longer present (Elia, 1999, 2004; Rey, 2003). Several different research groups have documented differences from control solvents of the remedies themselves or of remedy effects at above-Avogadro number dilutions (with succussions) in animals, plants, or cell preparations (Belougne-Malfatti, Aguejouf, Doutremepuich, Belon, & Doutremepuich, 1998; Doutremepuich, Aguejouf, Pintigny, Sertillanges, & De Seze, 1994; Hamman, Koning, & Lok, 2003; W. Jonas, Lin, & Tortella, 2001; W. B. Jonas, 1999; Marotta et al., 2002; N. C. Sukul, Bala, S.K., Bhattacharyya, B., 1986; N. C. Sukul, Ghosh, Sinhababu, & Sukul, 2001; Van Wijk & Wiegant, 1997; Werkman, 2006).

Theories of mediation include changes in hydrogen bonding and/or van der waals forces between the dynamical interactive network of water/solvent molecules (not the structure of any single water molecule). Other documented phenomena such as epitaxy are also testable hypotheses (Roy, Tiller, Bell, & Hoover, 2005). Silica contaminants released from the walls of glass containers during succussion may contribute to the generation and/or stabilization of remedies, but not necessarily to explaining the unique signatures of specific individual remedies in comparison with succussed solvent controls or other remedies (Ives et al. presentation at the North American Research Conference on Complementary and Alternative Medicine, Edmonton, AB , Canada, May 24-27, 2006).

Another key aspect of remedy response is potentially the phenomenon of hormesis, or nonlinear dose-response relationships that occur below the lowest observed level for adverse effects of many different agents, including radiation, toxins, and various drugs (E. J. Calabrese, 2005; E. J. Calabrese, Baldwin, L.A., 2001). Low doses of agents under certain conditions can cause effects on a biological system opposite in direction to those of high doses of the same agent. For homeopathy, this well-documented phenomenon is likely relevant to the healing responses of people, plants, and animals to remedies, but little research on hormesis per se has addressed homeopathically-prepared remedies.

In addition, the timing of the dose relative to an injury may contribute to nonlinear dose-response relationships in homeopathy. One study in animals, for example, found that giving a mineral remedy mixture lessened experimentally-induced swelling in paws when given after the injury occurred, but the same remedy and potenties worsened the swelling when given before the injury occurred (Bertani, Lussignoli, Andrioli, Bellavite, & Conforti, 1999). Such research deserves much additional study of state-dependent effects to determine the circumstances under which it is helpful – or potentially harmful – to administer remedies.

Several different homeopathic research groups have converged on suggesting that modern complex systems and network theory may assist in translating homeopathic theory and practice into a scientifically accessible framework (Bell, Baldwin, & Schwartz, 2002; Bell & Koithan, 2006; Bell, Lewis, Lewis et al., 2004; P. Bellavite, 2003; P. Bellavite, Signorini, A., 2002; M. Hyland, 2003; M. E. Hyland & Lewith, 2002; Milgrom, 2002; Torres, 2002; Torres & Ruiz, 1996). Systems theory may provide a bridge between the basic science research and clinical observations in homeopathic practice that can advance the field in both broad areas.

(2) Improving Homeopathic Practice Papers

Provings Research

Provings are the foundation of drug development in the field of homeopathy, but systematic research has raised concerns about the reliability and reproducibility of the information generated. In some studies, the issue is that conventional statistical approaches in which symptom tallies are used show no differences between active (verum remedy) and placebo under controlled conditions.

Some investigators have said that such data analysis is inappropriate for studying homeopathy, as it is patterns of change, not lists of changes, that the more qualitative aspects of provings generate. It is also important to acknowledge that conventional health psychology research has consistently shown that even generally “healthy” people generate a low level of symptoms on a regular basis, thereby making some observation of symptom patterns in the absence of remedy essential in order to avoid confusing spontaneous symptoms with those related to remedy action.

Any novice homeopath can attest that the remedies all seem to blur together and seem all alike, if he/she is looking for a treatment for an isolated symptom.  Thus, both the symptom pattern and time course pattern may be critical in ecologically valid provings research. Use of qualitative research methods may also be essential for improving the quality of the generated information

Other investigators have raised more fundamental theoretical concerns, i.e., that the remedy,  the remedy symptoms, the placebo, and provers are all entangled in a macro- way in the real world, just as quantum physicists have demonstrated entanglement at the quantum level of analysis. Such a possibility offers one explanation why leading homeopaths who do provings research report seeing unique symptoms of the active/verum remedy occurring in persons receiving placebo or just in participating in the same training workshop where other people are taking the remedy.

Therefore, it is important for any homeopath who undertakes provings research to educate him/herself about the issues and consider design options for dealing with both the issue of patterns and the possibility of macro-quantum entanglement as confounders of the work.

References to inform homeopaths who choose to work on provings are listed below.

Clinical Practice Studies

One of the most noticeable lacks in the homeopathic research literature is studies addressing how to improve clinical practice. Most of the clinical literature is concerned with presenting individual case reports in detail, but rarely do clinical investigators look at how to optimize patient outcomes during homeopathic treatment as a broad question.

One recent and notable exception has been a series of papers by Frei et al. on attention deficit disorder, in which they looked at strategies for improving patient outcomes (H. Frei et al., 2006). Their paper opens the door on a huge need in the field of homeopathic research that could begin to lessen opinion-based homeopathic practice and strengthen evidence-based and clinically-relevant homeopathic practice. Any one system from any particular master homeopath likely has internal validity, but when should practitioners apply one approach versus another? Do allopathic diagnosis, patient characteristics, homeopath characteristics, specific remedy kingdom or remedy family etc. influence outcomes? These are pressing questions that research can and should address.

Conclusions

The research literature on homeopathy is growing and improving in quality. However, for various reasons, the field is still young in terms of developing appropriate methodologies for the unique nature of homeopathy as a complex intervention and whole system of care. Advances in both theory and empirical work are bringing us closer to useful data for application in everyday homeopathic practice. In the meantime, serious students of homeopathy and practitioners need to monitor developments on the research front that may help them carry out their difficult challenge of meeting Hahnemann’s original charge to the profession, i.e., “…to make the sick healthy, to cure as it is termed.”

References

Aickin, M. (2005). The end of biomedical journals: there is madness in their methods. Journal of Alternative & Complementary Medicine, 11(5), 755-757.

Andrade, L. E., Ferraz, M. B., Atra, E., Castro, A., & Silva, M. S. (1991). A randomized controlled trial to evaluate the effectiveness of homeopathy in rheumatoid arthritis. Scandinavian Journal of Rheumatology., 20(3), 204-208.

Anelli, M., Scheepers, L., Sermeus, G., & Van Wassenhoven, M. (2002). Homeopathy and health related Quality of Life: a survey in six European countries. Homeopathy: the Journal of the Faculty of Homeopathy., 91(1), 18-21.

Bell, I. R. (2003). Evidence-based homeopathy: empirical questions and methodological considerations for homeopathic clinical research. American Journal of Homeopathic Medicine, 96(1), 17-31.

Bell, I. R. (2005). All evidence is equal, but some evidence is more equal than others: can logic prevail over emotion in the homeopathy debate? J Altern Complement Med., 11(5), 763-769.

Bell, I. R. (2005). Depression research in homeopathy: hopeless or hopeful? Homeopathy: Journal of the Faculty of Homeopathy., 94, 141-144.

Bell, I. R., Baldwin, C. M., & Schwartz, G. E. (2002). Translating a nonlinear systems theory model for homeopathy into empirical tests. Alternative Therapies in Health & Medicine., 8(3), 58-66.

Bell, I. R., DA, L., AJ, B., S, L., CM, B., & GE, S. (2005). Heart rate variability changes in fibromyalgia patients treated with individualized homeopathy., 2nd Annual ISSSEEM Research Symposium on Energetic and Spiritual Processes in Healing. Colorado Springs, CO.

Bell, I. R., & Koithan, M. (2006). Models for the study of whole systems. Integrative Cancer Therapies, 5(4), 293-307.

Bell, I. R., Koithan, M., Gorman, M. M., & Baldwin, C. M. (2003). Homeopathic practitioner views of changes in patients undergoing constitutional treatment for chronic disease. Journal of Alternative & Complementary Medicine, 9(1), 39-50.

Bell, I. R., Lewis, D. A., 2nd, Brooks, A. J., Schwartz, G. E., Lewis, S. E., Caspi, O., et al. (2004). Individual differences in response to randomly assigned active individualized homeopathic and placebo treatment in fibromyalgia: implications of a double-blinded optional crossover design. Journal of Alternative & Complementary Medicine, 10(2), 269-283.

Bell, I. R., Lewis, D. A., 2nd, Brooks, A. J., Schwartz, G. E., Lewis, S. E., Walsh, B. T., et al. (2004). Improved clinical status in fibromyalgia patients treated with individualized homeopathic remedies versus placebo. Rheumatology, 43(5), 577-582.

Bell, I. R., Lewis, D. A., 2nd, Lewis, S. E., Schwartz, G. E., Brooks, A. J., Scott, A., et al. (2004). EEG alpha sensitization in individualized homeopathic treatment of fibromyalgia. International Journal of Neuroscience, 114(9), 1195-1220.

Bell, I. R., Lewis, D. A. I., Lewis, S. E., Brooks, A. J., Schwartz, G. E., & Baldwin, C. M. (2004). Strength of vital force in classical homeopathy: bio-psycho-social-spiritual correlates in a complex systems context. J Alternative and Complementary Medicine, 10(1), 123-131.

Bell, I. R., Lewis, D. A. I., Schwartz, G. E., Lewis, S. E., Caspi, O., Scott, A., et al. (2004). Electroencephalographic cordance patterns distinguish exceptional clinical responders with fibromyalgia to individualized homeopathic medicines. J Alternative & Complementary Medicine, 10(2), 285-299.

Bellavite, P. (2003). Complexity science and homeopathy: a synthetic overview. Homeopathy: the Journal of the Faculty of Homeopathy., 92(4), 203-212.

Bellavite, P., Signorini, A. (2002). The Emerging Science of Homeopathy.  Complexity, Biodynamics, and Nanopharmacology (2nd ed.). Berkeley: North Atlantic Books.

Belougne-Malfatti, E., Aguejouf, O., Doutremepuich, F., Belon, P., & Doutremepuich, C. (1998). Combination of two doses of acetyl salicylic acid: experimental study of arterial thrombosis. Thrombosis Research., 90(5), 215-221.

Bertani, S., Lussignoli, S., Andrioli, G., Bellavite, P., & Conforti, A. (1999). Dual effects of a homeopathic mineral complex on carrageenan-induced oedema in rats. British Homoeopathic Journal, 88(3), 101-105.

Biswas, S. J., & Khuda-Bukhsh, A. R. (2004). Evaluation of protective potentials of a potentized homeopathic drug, Chelidonium majus, during azo dye induced hepatocarcinogenesis in mice. Indian Journal of Experimental Biology, 42(7), 698-714.

Bonne, O., Shemer, Y., Gorali, Y., Katz, M., & Shalev, A. Y. (2003). A randomized, double-blind, placebo-controlled study of classical homeopathy in generalized anxiety disorder. Journal of Clinical Psychiatry., 64(3), 282-287.

Bornhoft, G., Wolf U, Ammon K, Righetti M, Maxion-Bergemann S, Baumgartner S, Thurneysen AE, Matthiessen PF. (2006). Effectiveness, safety and cost-effectiveness of homeopathy in general practice - summarized health technology assessment. Forsch Komplementarmed., 13(Suppl 2), 19-29.

Breuer, G. S., Orbach, H., Elkayam, O., Berkun, Y., Paran, D., Mates, M., et al. (2005). Perceived efficacy among patients of various methods of complementary alternative medicine for rheumatologic diseases. Clinical & Experimental Rheumatology, 23(5), 693-696.

Buettner, C., Kroenke CH, Phillips RS, Davis RB, Eisenberg DM, Holmes MD. (2006). Correlates of use of different types of complementary and alternative medicine by breast cancer survivors in the nurses' health study. Breast Cancer Res Treat., 100(2), 219-227.

Calabrese, E. J. (2005). Toxicological awakenings: the rebirth of hormesis as a central pillar of toxicology. [Review] [62 refs]. Toxicology & Applied Pharmacology, 204(1), 1-8.

Calabrese, E. J., Baldwin, L.A. (2001). Hormesis: a generalizable and unifying hypothesis. Critical Reviews in Toxicology, 31, 353-424.

Caulfield, T., DeBow S. (2005). A systematic review of how homeopathy is represented in conventional and CAM peer reviewed journals. BMC Complement Altern Med., 5(1), 12.

Chapman, E. H., Weintraub, R. J., Milburn, M. A., Pirozzi, T. O., & Woo, E. (1999). Homeopathic treatment of mild traumatic brain injury: A randomized, double-blind, placebo-controlled clinical trial. Journal of Head Trauma Rehabilitation, 14(6), 521-542.

Chapman, E. H., & Wilson, J. J. (1999). Homeopathy in rehabilitation medicine. Physical Medicine & Rehabilitation Clinics of North America, 10(3), 705-727, x.

Clover, A., & Ratsey, D. (2002). Homeopathic treatment of hot flushes: a pilot study. Homeopathy: the Journal of the Faculty of Homeopathy, 91(2), 75-79.

Concato, J. (2004). Observational versus experimental studies: what's the evidence for a hierarchy? NeuroRx. , 1(3), 341-347.

Concato, J., Horwitz, R.I. (2004). Beyond randomised versus observational studies. Lancet., 363(9422), 1660-1661.

Concato, J., Shah, N., & Horwitz, R. I. (2000). Randomized, controlled trials, observational studies, and the hierarchy of research designs. New England Journal of Medicine., 342(25), 1887-1892.

Cucherat, M., Haugh, M. C., Gooch, M., & Boissel, J. P. (2000). Evidence of clinical efficacy of homeopathy. A meta-analysis of clinical trials. HMRAG. Homeopathic Medicines Research Advisory Group. European Journal of Clinical Pharmacology, 56(1), 27-33.

Davidson, J. R., Morrison, R. M., Shore, J., Davidson, R. T., & Bedayn, G. (1997). Homeopathic treatment of depression and anxiety.[see comment]. Alternative Therapies in Health & Medicine, 3(1), 46-49.

Dean, M. E., Coulter, M. K., Fisher, P., Jobst, K., & Walach, H. (2006). Reporting Data on Homeopathic Treatments (RedHot): A Supplement to CONSORT*. Forsch Komplementarmed., 13(6), 368-371.

Dominici, G., Bellavite, P., di Stanislao C, Gulia P, Pitari G. (2006). Double-blind, placebo-controlled homeopathic pathogenetic trials: symptom collection and analysis. Homeopathy., 95(3), 123-130.

Doutremepuich, C., Aguejouf, O., Pintigny, D., Sertillanges, M. N., & De Seze, O. (1994). Thrombogenic properties of ultra-low-dose of acetylsalicylic acid in a vessel model of laser-induced thrombus formation. Thrombosis Research., 76(2), 225-229.

Elia, V., Niccoli, M. (1999). Thermodynamics of extremely diluted aqueous solutions. Annals of the New York Academy of Sciences, 879, 241-248.

Elia, V., Niccoli, M. (2004). New physico-chemical properties of extremely diluted aqueous solutions. Journal of Thermal Analysis and Calorimetry, 75, 815-836.

Ernst, E. (2001). Complementary therapies in palliative cancer care. Cancer, 91(11), 2181-2185.

Ernst, E. (2002). A systematic review of systematic reviews of homeopathy. British Journal of Clinical Pharmacology., 54(6), 577-582.

Ernst, E., & Pittler, M. H. (1998). Efficacy of homeopathic arnica: a systematic review of placebo-controlled clinical trials. Archives of Surgery, 133(11), 1187-1190.

Fisher, P., Berman B, Davidson J, Reilly D, Thompson T. . (2005). Are the clinical effects of homoeopathy placebo effects? Lancet. , 366(9503), 2082-2083.

Fisher, P., Greenwood, A., Huskisson, E.C., Turner, P., Belon, P. (1989). Effect of homeopathic treatment on fibrositis (primary fibromyalgia). British Medical Journal., 299, 365-366.

Fisher, P., & Scott, D. L. (2001). A randomized controlled trial of homeopathy in rheumatoid arthritis. Rheumatology, 40(9), 1052-1055.

Frass, M., Linkesch, M., Banyai, S., Resch, G., Dielacher, C., Lobl, T., et al. (2005). Adjunctive homeopathic treatment in patients with severe sepsis: a randomized, double-blind, placebo-controlled trial in an intensive care unit. Homeopathy: the Journal of the Faculty of Homeopathy, 94(2), 75-80.

Freeman, A. C., & Sweeney, K. (2001). Why general practitioners do not implement evidence: qualitative study. Bmj, 323(7321), 1100-1102.

Frei, H., Everts R, von Ammon K, Kaufmann F, Walther D, Hsu-Schmitz SF, Collenberg M, Fuhrer K, Hassink R, Steinlin M, Thurneysen A. (2005). Homeopathic treatment of children with attention deficit hyperactivity disorder: a randomised, double blind, placebo controlled crossover trial. Eur J Pediatr., [Epub ahead of print].

Frei, H., Thurneysen A. (2001). Treatment for hyperactive children: homeopathy and methylphenidate compared in a family setting. British Homoeopathic Journal, 90(4), 183-188.

Frei, H., von Ammon, K., & Thurneysen, A. (2006). Treatment of hyperactive children: increased efficiency through modifications of homeopathic diagnostic procedure. Homeopathy., 95(3), 163-170.

Frenkel, M., & Hermoni, D. (2002). Effects of homeopathic intervention on medication consumption in atopic and allergic disorders. Altern Ther Health Med, 8(1), 76-79.

Geraghty, J. (2002). Homeopathic treatment of Chronic Fatigue Syndrome: three case studies using Jan Scholten's methodology. Homeopathy: the Journal of the Faculty of Homeopathy., 91(2), 99-105.

Gibson, R. G., Gibson, S. L., MacNeill, A. D., & Buchanan, W. W. (1980). Homoeopathic therapy in rheumatoid arthritis: evaluation by double-blind clinical therapeutic trial. British Journal of Clinical Pharmacology., 9(5), 453-459.

Goldstein, M. S., Glik, D. (1998). Use of and satisfaction with homeopathy in a patient population. Alternative Therapies in Health & Medicine, 4(2), 60-65.

Hamman, B., Koning, G., & Lok, K. H. (2003). Homeopathically prepared gibberellic acid and barley seed germination. Homeopathy: the Journal of the Faculty of Homeopathy, 92(3), 140-144.

Harrison, H., Fixsen, A., & Vickers, A. (1999). A randomized comparison of homoeopathic and standard care for the treatment of glue ear in children. Complementary Therapies in Medicine, 7(3), 132-135.

Hyland, M. (2003). Extended network generalized entanglement theory: therapeutic mechanisms, empirical predictions, and investigations. Journal of Alternative & Complementary Medicine, 9(6), 919-936.

Hyland, M. E., & Lewith, G. T. (2002). Oscillatory effects in a homeopathic clinical trial: an explanation using complexity theory, and implications for clinical practice. Homeopathy, 91(3), 145-149.

Jacobs, J., Guthrie BL, Montes GA, Jacobs LE, Mickey-Colman N, Wilson AR, DiGiacomo R. (2006). Homeopathic combination remedy in the treatment of acute childhood diarrhea in honduras. J Altern Complement Med., 12(8), 723-732.

Jacobs, J., Herman, P., Heron, K., Olsen, S., & Vaughters, L. (2005). Homeopathy for menopausal symptoms in breast cancer survivors: a preliminary randomized controlled trial. Journal of Alternative and Complementary Medicine, 11(1), 21-27.

Jacobs, J., Jimenez, L. M., Gloyd, S. S., Gale, J. L., & Crothers, D. (1994). Treatment of acute childhood diarrhea with homeopathic medicine: a randomized clinical trial in Nicaragua. Pediatrics., 93(5), 719-725.

Jacobs, J., Jonas, W. B., JimAnez, P. M., & Crothers, D. (2003). Homeopathy for childhood diarrhea: combined results and metaanalysis from three randomized, controlled clinical trials. Pediatric Infectious Disease Journal, 22(3), 229-234.

Jacobs, J., Jonas, W. B., Jimenez-Perez, M., & Crothers, D. (2003). Homeopathy for childhood diarrhea: combined results and metaanalysis from three randomized, controlled clinical trials. Pediatric Infectious Disease Journal, 22(3), 229-234.

Jacobs, J., Springer, D.A., Crothers, D. (2001). Homeopathic treatment of acute otitis media in children: a preliminary randomized, placebo-controlled trial. Pediatric Infectious Disease Journal, 20, 177-183.

Jacobs, J., Williams, A. L., Girard, C., V.Y., N., & Katz, D. (2005). Homeopathy for attention-deficit/hyperactivity disorder: a pilot randomized controlled trial. Journal of Alternative & Complementary Medicine, 11(5), 799-806.

Jonas, W., Lin, Y., & Tortella, F. (2001). Neuroprotection from glutamate toxicity with ultra-low dose glutamate. Neuroreport, 12(2), 335-339.

Jonas, W., Lin, Y., Williams, A., Tortella, F., Tuma, R. (1999). Treatment of experimental stroke with low-dose glutamate and homeopathic Arnica montana. Perfusion, 12, 452-462.

Jonas, W. B. (1999). Do homeopathic nosodes protect against infection? An experimental test. Alternative Therapies in Health & Medicine, 5(5), 36-40.

Jonas, W. B., Linde, K., & Ramirez, G. (2000). Homeopathy and rheumatic disease. Rheumatic Diseases Clinics of North America, 26(1), 117-123, x.

Katz, T., Fisher, P., Katz, A., Davidson, J., & Feder, G. (2005). The feasibility of a randomised, placebo-controlled clinical trial of homeopathic treatment of depression in general practice. Homeopathy.

Kim, L. S., Riedlinger, J. E., Baldwin, C. M., Hilli, L., Khalsa, S. V., Messer, S. A., et al. (2005). Treatment of Seasonal Allergic Rhinitis Using Homeopathic Preparation of Common Allergens in the Southwest Region of the US: A Randomized, Controlled Clinical Trial. Annals of Pharmacotherapy, 39(4), 617-624.

Kleijnen, J., Knipschild, P., & ter Riet, G. (1991). Clinical trials of homoeopathy. Bmj., 302(6772), 316-323.

Lamont, J. (1997). Homeopathic treatment of attention deficit hyperactivity disorder. A controlled study. British Homoeopathic Journal, 86, 196-200.

Lancet, T. (2005). The end of homeopathy. Lancet., 366, 690.

Lewith, G. T., Brien, S., & Hyland, M. E. (2005). Presentiment or entanglement? An alternative explanation for apparent entanglement in provings. [Review] [17 refs]. Homeopathy: the Journal of the Faculty of Homeopathy, 94(2), 92-95.

Lewith, G. T., Watkins, A. D., Hyland, M. E., Shaw, S., Broomfield, J. A., Dolan, G., et al. (2002). Use of ultramolecular potencies of allergen to treat asthmatic people allergic to house dust mite: double blind randomised controlled clinical trial. BMJ, 324(7336), 520-523.

Linde, K., Clausius, N., Ramirez, G., Melchart, D., F., E., Hedges, L. V., et al. (1997). Are the clinical effects of homeopathy placebo effects?  A meta-analysis of placebo-controlled trials. Lancet, 350, 834-843.

Linde, K., & Jobst, K. A. (2000). Homeopathy for chronic asthma. Cochrane Database of Systematic Reviews [computer file](2), CD000353.

MacLaughlin, B. W., Gutsmuths B, Pretner E, Jonas WB, Ives J, Kulawardane DV, et al. (2006). Effects of homeopathic preparations on human prostate cancer growth in cellular and animal models. Integr Cancer Ther., 5(4), 362-372.

Marotta, D., Marini, A., Banaudha, K., Maharaj, S., Ives, J., Morrissette, C. R., et al. (2002). Non-linear effects of cycloheximide in glutamate-treated cultured rat cerebellar neurons. Neurotoxicology., 23(3), 307-312.

Mastrangelo, D. (2006). Hormesis, epitaxy, the structure of liquid water, and the science of homeopathy. Med Sci Monit., 13(1), SR1-8.

Maxion-Bergemann, S., Wolf, M., Bornhoft, G., Matthiessen, P. F., & Wolf, U. (2006). Complementary and alternative medicine costs - a systematic literature review. Forsch Komplementarmed., 13(Suppl 2), 42-45.

Milgrom, L. R. (2002). Vitalism, complexity, and the concept of spin. Homeopathy: the Journal of the Faculty of Homeopathy., 91(1), 26-31.

Milgrom, L. R. (2004). Patient-Practitioner-Remedy (PPR) Entanglement, Part 7: a gyroscopic metaphor for the vital force and its use to illustrate some of the empirical laws of homeopathy. 212-223, 2004 Aug.

Milgrom, L. R. (2005). Patient-Practitioner-Remedy (PPR) entanglement, Part 8: 'Laser-like' action of the homeopathic therapeutic encounter as predicted by a gyroscopic metaphor for the vital force. Forschende Komplementarmedizin und Klassische Naturheilkunde, 12(4), 206-213.

Milgrom, L. R. (2006a). Entanglement, knowledge, and their possible effects on the outcomes of blinded trials of homeopathic provings. J Altern Complement Med., 12(3), 271-279.

Milgrom, L. R. (2006b). Is homeopathy possible? J R Soc Health., 126(5), 211-218.

Molassiotis, A., Fernadez-Ortega, P., Pud, D., Ozden, G., Scott, J. A., Panteli, V., et al. (2005). Use of complementary and alternative medicine in cancer patients: a European survey. Annals of Oncology, 16(4), 655-663.

Montfort, H. (2000). A new homeopathic approach to neoplastic diseases: from cell destruction to carcinogen-induced apoptosis. British Homoeopathic Journal, 89(2), 78-83.

Morawiec-Bajda, A., Lukomski, M., & Latkowski, B. (1993). The clinical efficacy of Vertigoheel in the treatment of vertigo of various etiology. Panminerva Medica., 35(2), 101-104.

Oberbaum, M., Galoyan, N., Lerner-Geva, L., Singer, S. R., Grisaru, S., Shashar, D., et al. (2005). The effect of the homeopathic remedies Arnica montana and Bellis perennis on mild postpartum bleeding--a randomized, double-blind, placebo-controlled study--preliminary results. Complementary Therapies in Medicine, 13(2), 87-90, 2005 Jun.

Oberbaum, M., Singer SR, Frass M. . (2005). Homeopathic research after the Lancet meta analysis--a moment for introspection. Complement Ther Med., 13(4), 303-305.

Oberbaum, M., Singer SR, Vithoulkas G. (2005). The colour of the homeopathic improvement: the multidimensional nature of the response to homeopathic therapy. Homeopathy., 94(3), 196-199.

Oberbaum, M., Yaniv, I., Ben-Gal, Y., Stein, J., Ben-Zvi, N., Freedman, L. S., et al. (2001). A randomized, controlled clinical trial of the homeopathic medication TRAUMEEL S in the treatment of chemotherapy-induced stomatitis in children undergoing stem cell transplantation. Cancer, 92(3), 684-690.

Pilkington, K., Kirkwood, G., Rampes, H., Fisher, P., & Richardson, J. (2005). Homeopathy for depression: a systematic review of the research evidence. Homeopathy.

Pilkington, K., Kirkwood G, Rampes H, Fisher P, Richardson J. (2006). Homeopathy for anxiety and anxiety disorders: a systematic review of the research. Homeopathy. 2006 Jul;95(3):151-62., 95(3), 151-162.

Ramelet, A. A., Buchheim, G., Lorenz, P., & Imfeld, M. (2000). Homeopathic Arnica in postoperative haematomas: a double-blind study. Dermatology., 201(4), 347-348.

Rastogi, D. P., Singh, V. P., Singh, V., Dey, S. K., & Rao, K. (1999). Homeopathy in HIV infection: a trial report of double-blind placebo controlled study. British Homoeopathic Journal, 88(2), 49-57.

Reilly, D., Taylor, M.A., Beattie, N.G.M., Campbell, J.H., McSharry, C., Aitchison, T.C., Carter, R., Stevenson, R.D. (1994). Is evidence for homeopathy reproducible? Lancet, 344, 1601-1606.

Reilly, D. T., Taylor, M. A., McSharry, C., & Aitchison, T. (1986). Is homoeopathy a placebo response? Controlled trial of homoeopathic potency, with pollen in hayfever as model. Lancet., 2(8512), 881-886.

Relton, C., & Weatherley-Jones, E. (2005). Homeopathy service in a National Health Service community menopause clinic: audit of clinical outcomes. Journal of the British Menopause Society, 11(2), 72-73.

Rey, L. (2003). Thermoluminescence of ultra-high dilutions of lithium chloride and sodium chloride. Physica A: Statistical mechanics and its applications., 323, 67-74.

Riley, D., Fischer, M., Singh, B., Haidvogl, M., & Heger, M. (2001). Homeopathy and conventional medicine: an outcomes study comparing effectiveness in a primary care setting. Journal of Alternative & Complementary Medicine, 7(2), 149-159.

Roy, R., Tiller, W., Bell, I. R., & Hoover, M. R. (2005). The Structure of Liquid Water: Novel Insights from Materials Research and Potential Relevance to Homeopathy. Materials Research Innovation, 9(4), 557-608.

Schlappack, O. (2004a). Homeopathic treatment of radiation-induced itching in breast cancer patients. A prospective observational study. Homeopathy: the Journal of the Faculty of Homeopathy, 93(4), 210-215.

Schlappack, O. (2004b). Homeopathic treatment of radiation-induced itching in breast cancer patients. A prospective observational study. Homeopathy. , 93(4), 210-215.

Sevar, R. (2000). Audit of outcome in 829 consecutive patients treated with homeopathic medicines. British Homoeopathic Journal, 89(4), 178-187.

Sevar, R. (2005). Audit of outcome in 455 consecutive patients treated with homeopathic medicines. Homeopathy., 94(4), 215-221.

Shang, A., Huwiler-Muntener, K., Nartey, L., Juni, P., Dorig, S., Sterne, J. A., et al. (2005). Are the clinical effects of homoeopathy placebo effects? Comparative study of placebo-controlled trials of homoeopathy and allopathy.[see comment]. Lancet, 366(9487), 726-732.

Spence, D. S., Thompson, E. A., & Barron, S. J. (2005). Homeopathic treatment for chronic disease: a 6-year, university-hospital outpatient observational study. J Altern Complement Med., 11(5), 793-798.

Steinsbekk, A., Bentzen, N., Fonnebo, V., & Lewith, G. (2004). The use of simplified constitutional indications for self-prescription of homeopathic medicine. Complementary Therapies in Medicine, 12(2-3), 112-117.

Steinsbekk, A., Bentzen, N., Fonnebo, V., & Lewith, G. (2005). Self treatment with one of three self selected, ultramolecular homeopathic medicines for the prevention of upper respiratory tract infections in children. A double-blind randomized placebo controlled trial. British Journal of Clinical Pharmacology, 59(4), 447-455.

Steinsbekk, A., & Ludtke, R. (2005). Patients' assessments of the effectiveness of homeopathic care in Norway: a prospective observational multicentre outcome study. Homeopathy, 94(1), 10-16.

Stevinson, C., Devaraj, V. S., Fountain-Barber, A., Hawkins, S., & Ernst, E. (2003). Homeopathic arnica for prevention of pain and bruising: randomized placebo-controlled trial in hand surgery. Journal of the Royal Society of Medicine., 96(2), 60-65.

Sukul, N. C., Bala, S.K., Bhattacharyya, B. (1986). Prolonged cataleptogenic effects of potentized homoeopathic drugs. Psychopharmacology, 89, 338-339.

Sukul, N. C., Ghosh, S., Sinhababu, S. P., & Sukul, A. (2001). Strychnos nux-vomica extract and its ultra-high dilution reduce voluntary ethanol intake in rats. Journal of Alternative & Complementary Medicine, 7(2), 187-193.

Taylor, M. A., Reilly, D., Llewellyn-Jones, R. H., McSharry, C., & Aitchison, T. C. (2000). Randomised controlled trial of homoeopathy versus placebo in perennial allergic rhinitis with overview of four trial series. Bmj, 321(7259), 471-476.

Thompson, E., Barron, S., & Spence, D. (2004). A preliminary audit investigating remedy reactions including adverse events in routine homeopathic practice. Homeopathy: the Journal of the Faculty of Homeopathy, 93(4), 203-209.

Thompson, E. A., Montgomery, A., Douglas, D., & Reilly, D. (2005). A pilot, randomized, double-blinded, placebo-controlled trial of individualized homeopathy for symptoms of estrogen withdrawal in breast-cancer survivors.[see comment]. Journal of Alternative & Complementary Medicine, 11(1), 13-20.

Thompson, T. D. (2004). Can the caged bird sing? Reflections on the application of qualitative research methods to case study design in homeopathic medicine. BMC Medical Research Methodology, 4(1), 4: http://www.biomedcentral.com/content/pdf/1471-2288-1474-1474.pdf.

Thompson, T. D., & Weiss, M. (2006). Homeopathy--what are the active ingredients? An exploratory study using the UK Medical Research Council's framework for the evaluation of complex interventions. BMC Complement Altern Med., 13(6), 37.

Torres, J. L. (2002). Homeopathic effect: a network perspective. Homeopathy: the Journal of the Faculty of Homeopathy., 91(2), 89-94.

Torres, J. L., & Ruiz, M. A. G. (1996). Stochastic resonance and the homeopathic effect. British Homoeopathic Journal, 85, 134-140.

Trichard, M., Chaufferin, G., & Nicoloyannis, N. (2005). Pharmacoeconomic comparison between homeopathic and antibiotic treatment strategies in recurrent acute rhinopharyngitis in children.[see comment]. Homeopathy: the Journal of the Faculty of Homeopathy, 94(1), 3-9.

Ullman, D. (2006). Let's have a serious discussion of nanopharmacology and homeopathy. The FASEB Journal, 20, 2661.

van Haselen, R. (2005). The end of homeopathy: wishful thinking? Complement Ther Med., 13(4), 229-230.

van Haselen, R. A., & Fisher, P. A. (2000). A randomized controlled trial comparing topical piroxicam gel with a homeopathic gel in osteoarthritis of the knee. Rheumatology, 39(7), 714-719.

van Wassenhoven, M., & Ives, G. (2004). An observational study of patients receiving homeopathic treatment. Homeopathy, 93(1), 3-11.

Van Wijk, R., & Wiegant, F. A. (1997). The similia principle as a therapeutic strategy: a research program on stimulation of self-defense in disordered mammalian cells. Alternative Therapies in Health & Medicine., 3(2), 33-38.

Vandenbroucke, J. P. (1997). Homeopathy trials:  going nowhere. Lancet, 350, 824.

Vickers, A. J., & Smith, C. (2004). Homoeopathic Oscillococcinum for preventing and treating influenza and influenza-like syndromes. Cochrane Database of Systematic Reviews [computer file], 1, CD001957.

Vickers, A. J., Smith C. (2006). Homoeopathic Oscillococcinum for preventing and treating influenza and influenza-like syndromes. Cochrane Database Syst Rev., 19(3), CD001957.

Viksveen, P. (2003). Antibiotics and the development of resistant microorganisms. Can homeopathy be an alternative?. [Review] [92 refs]. Homeopathy: the Journal of the Faculty of Homeopathy, 92(2), 99-107.

Walach, H. (1993). Does a highly diluted homoeopathic drug act as a placebo in healthy volunteers? Experimental study of Belladonna 30C in double-blind crossover design--a pilot study. Journal of Psychosomatic Research., 37(8), 851-860.

Walach, H. (2000). Magic of signs: a non-local interpretation of homeopathy. British Homoeopathic Journal, 89(3), 127-140.

Walach, H. (2002). What happens in homeopathic remedy provings? Results from a double-blind crossover study of belladonna 30CH and an analysis by grade of membership (GoM). In R. A. Chez (Ed.), Future Directions and Current Issues of Research in Homeopathy (pp. 110-133). Freiburg, Germany: Samueli Institute.

Walach, H. (2003). Entanglement model of homeopathy as an example of generalised entanglement predicted by weak quantum theory. Forschende Komplementarmedizin/Research in Complementary Medicine, 10(4), 192-200.

Walach, H., Haeusler, W., Lowes, T., Mussbach, D., Schamell, U., Springer, W., et al. (1997). Classical homeopathic treatment of chronic headaches. Cephalalgia, 17(2), 119-126.

Walach, H., Jonas, W.B. (2002). Homeopathy. In G. Lewith, Jonas, W.B., Walach, H. (Ed.), Clinical Research in Complementary Therapies (pp. 229-246). Edinburgh: Churchill Livingstone.

Walach, H., Koster, H., Hennig, T., & Haag, G. (2001). The effects of homeopathic belladonna 30CH in healthy volunteers -- a randomized, double-blind experiment. Journal of Psychosomatic Research, 50(3), 155-160.

Walach, H., Lowes, T., Mussbach, D., Schamell, U., Springer, W., Stritzl, G., et al. (2000). The long-term effects of homeopathic treatment of chronic headaches: 1 year follow up. Cephalalgia., 20(9), 835-837.

Walach, H., Lowes, T., Mussbach, D., Schamell, U., Springer, W., Stritzl, G., et al. (2001). The long-term effects of homeopathic treatment of chronic headaches: one year follow-up and single case time series analysis. British Homoeopathic Journal., 90(2), 63-72.

Walach, H., Sherr, J., Schneider, R., Shabi, R., Bond, A., & Rieberer, G. (2004). Homeopathic proving symptoms: result of a local, non-local, or placebo process? A blinded, placebo-controlled pilot study.[see comment]. Homeopathy, 93(4), 179-185.

Weatherley-Jones, E., Nicholl, J. P., Thomas, K. J., Parry, G. J., McKendrick, M. W., Green, S. T., et al. (2004). A randomised, controlled, triple-blind trial of the efficacy of homeopathic treatment for chronic fatigue syndrome.[see comment]. Journal of Psychosomatic Research, 56(2), 189-197.

Weissmann, G. (2006). Homeopathy: Holmes, Hogwarts, and the Prince of Wales. The FASEB Journal, 20, 1755-1758.

Werkman, C., Senra GS, da Rocha RF, Brandao AA. (2006). Comparative therapeutic use of Risedronate and Calcarea phosphorica--allopathy versus homeopathy--in bone repair in castrated rats. Pesqui Odontol Bras., 20(3), 196-201.

White, A., Slade, P., Hunt, C., Hart, A., & Ernst, E. (2003). Individualised homeopathy as an adjunct in the treatment of childhood asthma: a randomised placebo controlled trial. Thorax, 58(4), 317-321.

Witt, C., Keil, T., Selim, D., Roll, S., Vance, W., Wegscheider, K., et al. (2005). Outcome and costs of homoeopathic and conventional treatment strategies: a comparative cohort study in patients with chronic disorders. Complementary Therapies in Medicine, 13(2), 79-86.

Witt, C., Keil T, Selim D, Roll S, Vance W, Wegscheider K, Willich SN. (2005). Outcome and costs of homoeopathic and conventional treatment strategies: a comparative cohort study in patients with chronic disorders. Complement Ther Med., 13(2), 79-86.

Witt, C. M., Luedtke R, Baur R, Willich SN. (2005). Homeopathic Medical Practice: Long-term results of a Cohort Study with 3981 Patients. BMC Public Health., 5(1), 115 epub.

Yakir, M., Kreitler, S., Brzezinski, A., Vithoulkas, G., Oberbaum, M., & Bentwich, Z. (2001). Effects of homeopathic treatment in women with premenstrual syndrome: a pilot study.[see comment]. British Homoeopathic Journal, 90(3), 148-153.