Jürgen Clausen

Randomised placebo-controlled trials of individualised homeopathic treatment: systematic review and meta-analysis

BackgroundA rigorous and focused systematic review and meta-analysis of randomised controlled trials (RCTs) of individualised homeopathic treatment has not previously been undertaken. We tested the hypothesis that the outcome of an individualised homeopathic treatment approach using homeopathic medicines is distinguishable from that of placebos.MethodsThe review’s methods, including literature search strategy, data extraction, assessment of risk of bias and statistical analysis, were strictly protocol-based. Judgment in seven assessment domains enabled a trial’s risk of bias to be designated as low, unclear or high. A trial was judged to comprise ‘reliable evidence’ if its risk of bias was low or was unclear in one specified domain. ‘Effect size’ was reported as odds ratio (OR), with arithmetic transformation for continuous data carried out as required; OR > 1 signified an effect favouring homeopathy.ResultsThirty-two eligible RCTs studied 24 different medical conditions in total. Twelve trials were classed ‘uncertain risk of bias’, three of which displayed relatively minor uncertainty and were designated reliable evidence; 20 trials were classed ‘high risk of bias’. Twenty-two trials had extractable data and were subjected to meta-analysis; OR = 1.53 (95% confidence interval (CI) 1.22 to 1.91). For the three trials with reliable evidence, sensitivity analysis revealed OR = 1.98 (95% CI 1.16 to 3.38).ConclusionsMedicines prescribed in individualised homeopathy may have small, specific treatment effects. Findings are consistent with sub-group data available in a previous ‘global’ systematic review. The low or unclear overall quality of the evidence prompts caution in interpreting the findings. New high-quality RCT research is necessary to enable more decisive interpretation.

Randomised controlled trials of veterinary homeopathy: characterising the peer-reviewed research literature for systematic review.

INTRODUCTION Systematic review of the research evidence in veterinary homeopathy has never previously been carried out. This paper presents the search methods, together with categorised lists of retrieved records, that enable us to identify the literature that is acceptable for future systematic review of randomised controlled trials (RCTs) in veterinary homeopathy. METHODS All randomised and controlled trials of homeopathic intervention (prophylaxis and/or treatment of disease, in any species except man) were appraised according to pre-specified criteria. The following databases were systematically searched from their inception up to and including March 2011: AMED; Carstens-Stiftung Homeopathic Veterinary Clinical Research (HomVetCR) database; CINAHL; Cochrane Central Register of Controlled Trials; Embase; Hom-Inform; LILACS; PubMed; Science Citation Index; Scopus. RESULTS One hundred and fifty records were retrieved; 38 satisfied the acceptance criteria (substantive report of a clinical treatment or prophylaxis trial in veterinary homeopathic medicine randomised and controlled and published in a peer-reviewed journal), and were thus eligible for future planned systematic review. Approximately half of the rejected records were theses. Seven species and 27 different species-specific medical conditions were represented in the 38 papers. Similar numbers of papers reported trials of treatment and prophylaxis (n=21 and n=17 respectively) and were controlled against placebo or other than placebo (n=18, n=20 respectively). Most research focused on non-individualised homeopathy (n=35 papers) compared with individualised homeopathy (n=3). CONCLUSION The results provide a complete and clarified view of the RCT literature in veterinary homeopathy. We will systematically review the 38 substantive peer-reviewed journal articles under the main headings: treatment trials; prophylaxis trials.

Veterinary homeopathy: systematic review of medical conditions studied by randomised placebo-controlled trials

A systematic review of randomised controlled trials (RCTs) of veterinary homeopathy has not previously been undertaken. Using Cochrane methods, this review aims to assess risk of bias and to quantify the effect size of homeopathic intervention compared with placebo for each eligible peer-reviewed trial. Judgement in seven assessment domains enabled a trials risk of bias to be designated as low, unclear or high. A trial was judged to comprise reliable evidence if its risk of bias was low or was unclear in specified domains. A trial was considered to be free of vested interest if it was not funded by a homeopathic pharmacy. The 18 eligible RCTs were disparate in nature, representing four species and 11 different medical conditions. Reliable evidence, free from vested interest, was identified in two trials: homeopathic Coli had a prophylactic effect on porcine diarrhoea (odds ratio 3.89, 95 per cent confidence interval [CI], 1.19 to 12.68, P=0.02); and individualised homeopathic treatment did not have a more beneficial effect on bovine mastitis than placebo intervention (standardised mean difference -0.31, 95 per cent CI, -0.97 to 0.34, P=0.35). Mixed findings from the only two placebo-controlled RCTs that had suitably reliable evidence precluded generalisable conclusions about the efficacy of any particular homeopathic medicine or the impact of individualised homeopathic intervention on any given medical condition in animals.

The rat in basic therapeutic research in homeopathy

The Similia Principle, the basis of homeopathy, implies that substances initiating symptoms when applied to healthy biological systems can be utilized as remedies to treat a diseased system with similar symptoms. Depending whether the remedy substance was of the same type as the etiologic agent, treatment is classified as either homologous or heterologous. The intact rat is the biological system most utilized in basic science homeopathic research. The Homeopathy Basic Research experiments (HomBRex) database (about 1300 experiments on model biological systems in homeopathic research) was analyzed for homologous and heterologous treatments of disease states of intact rats. The relationship between the Similia Principle and hormesis is discussed.

Review of the use of high potencies in basic research on homeopathy

The HomBRex database includes details of about 1500 basic research experiments in homeopathy. A general overview on the experiments listed in the HomBRex database is presented, focusing on high dilutions and the different settings in which those were used. Though often criticised, many experiments with remedies diluted beyond Avogadros number demonstrate specific effects. A total of 830 experiments employing high potencies was found; in 745 experiments of these (90%), at least one positive result was reported. Animals represent the most often used model system (n=371), followed by plants (n=201), human material (n=92), bacteria and viruses (n=37) and fungi (n=32). Arsenicum album (Ars.) is the substance most often applied (n=101), followed by Sulphur (Sulph.) and Thuja (Thuj.) (n=65 and 48, respectively). Proving, prophylactic and therapeutic study designs have all been used and appear appropriate for homeopathy basic research using high dilutions. The basic research data set to support specific effects unique to high dilutions and opposite to those observed with low dilutions is, to date, insufficient.

Randomised, double-blind, placebo-controlled trials of non-individualised homeopathic treatment: systematic review and meta-analysis

BackgroundA rigorous systematic review and meta-analysis focused on randomised controlled trials (RCTs) of non-individualised homeopathic treatment has not previously been reported. We tested the null hypothesis that the main outcome of treatment using a non-individualised (standardised) homeopathic medicine is indistinguishable from that of placebo. An additional aim was to quantify any condition-specific effects of non-individualised homeopathic treatment.MethodsLiterature search strategy, data extraction and statistical analysis all followed the methods described in a pre-published protocol. A trial comprised ‘reliable evidence’ if its risk of bias was low or it was unclear in one specified domain of assessment. ‘Effect size’ was reported as standardised mean difference (SMD), with arithmetic transformation for dichotomous data carried out as required; a negative SMD indicated an effect favouring homeopathy.ResultsForty-eight different clinical conditions were represented in 75 eligible RCTs. Forty-nine trials were classed as ‘high risk of bias’ and 23 as ‘uncertain risk of bias’; the remaining three, clinically heterogeneous, trials displayed sufficiently low risk of bias to be designated reliable evidence. Fifty-four trials had extractable data: pooled SMD was –0.33 (95% confidence interval (CI) –0.44, –0.21), which was attenuated to –0.16 (95% CI –0.31, –0.02) after adjustment for publication bias. The three trials with reliable evidence yielded a non-significant pooled SMD: –0.18 (95% CI –0.46, 0.09). There was no single clinical condition for which meta-analysis included reliable evidence.ConclusionsThe quality of the body of evidence is low. A meta-analysis of all extractable data leads to rejection of our null hypothesis, but analysis of a small sub-group of reliable evidence does not support that rejection. Reliable evidence is lacking in condition-specific meta-analyses, precluding relevant conclusions. Better designed and more rigorous RCTs are needed in order to develop an evidence base that can decisively provide reliable effect estimates of non-individualised homeopathic treatment.

Veterinary Clinical Research Database for Homeopathy: Placebo-controlled trials

BACKGROUND Veterinary homeopathy has led a somewhat shadowy existence since its first introduction. Only in the last three decades has the number of clinical trials increased considerably. This literature is generally not well perceived, which may be partly a consequence of the diffuse and somewhat inaccessible nature of some of the relevant research publications. The Veterinary Clinical Research Database for Homeopathy (VetCR) was launched in 2006 to provide information on existing clinical research in veterinary homeopathy and to facilitate the preparation of systematic reviews. OBJECTIVE The aim of the present report is to provide an overview of this first database on clinical research in veterinary homeopathy, with a special focus on its content of placebo controlled clinical trials and summarising what is known about placebo effects in animals. RESULTS In April 2012, the VetCR database contained 302 data records. Among these, 203 controlled trials were identified: 146 randomised and 57 non-randomised. In 97 of those 203 trials, the homeopathic medical intervention was compared to placebo. COMMENT A program of formal systematic reviews of peer-reviewed randomised controlled trials in veterinary homeopathy is now underway; detailed findings from the programs data extraction and appraisal approach, including the assessment of trial quality (risk of bias), will be reported in due course.

CORE-Hom: A powerful and exhaustive database of clinical trials in homeopathy

The CORE-Hom database was created to answer the need for a reliable and publicly available source of information in the field of clinical research in homeopathy. As of May 2014 it held 1048 entries of clinical trials, observational studies and surveys in the field of homeopathy, including second publications and re-analyses. 352 of the trials referenced in the database were published in peer reviewed journals, 198 of which were randomised controlled trials. The most often used remedies were Arnica montana (n = 103) and Traumeel(®) (n = 40). The most studied medical conditions were respiratory tract infections (n = 126) and traumatic injuries (n = 110). The aim of this article is to introduce the database to the public, describing and explaining the interface, features and content of the CORE-Hom database.

Infection models in basic research on homeopathy

INTRODUCTION The objective of this study was to search for effective agents for the treatment of infections in animals or infected cell lines. METHODS The Homeopathic Basic Research experiments (HomBRex) database (http://www.carstens-stiftung.de/hombrex) on model biological systems in homeopathic research was searched. Eligible experiments were reviewed and analysed. RESULTS The database contains 48 eligible experiments published from 1832 to 2009. Causative pathogens were bacteria, fungi, viruses, proto- and metazoa. In the experiments, various parameters were observed and a large set of medicines was investigated. In eight of the 48 experiments, at least one of the investigated medicines was selected according to the similia principle. Nosodes and homeopathic complexes were investigated in 8 and 14 experiments respectively. Mice were the most often used host organisms (13 experiments). In 31 experiments at least one homeopathic medicine was found effective for treatment. CONCLUSION The results of basic research experiments may invigorate new clinical trials that investigate complementary treatments for infectious diseases. However, all experiments reviewed here await replication and no clear-cut conclusion can be drawn regarding the transferability of in vitro results to in vivo outcomes.

Veterinary homeopathy: Systematic review of medical conditions studied by randomised trials controlled by other than placebo

BackgroundNo systematic review has previously been carried out on randomised controlled trials (RCTs) of veterinary homeopathy in which the control group was an intervention other than placebo (OTP). For eligible peer-reviewed RCTs, the objectives of this study were to assess the risk of bias (RoB) and to quantify the effect size of homeopathic intervention compared with an active comparator or with no treatment.MethodsOur systematic review approach complied fully with the PRISMA 2009 Checklist. Cochrane methods were applied to assess RoB and to derive effect size using standard meta-analysis methods. Based on a thorough and systematic literature search, the following key attributes of the published research were distinguished: individualised homeopathy (n = 1 RCT)/non-individualised homeopathy (n = 19); treatment (n = 14)/prophylaxis (n = 6); active controls (n = 18)/untreated controls (n = 2). The trials were highly diverse, representing 12 different medical conditions in 6 different species.ResultsNo trial had sufficiently low RoB to be judged as reliable evidence: 16 of the 20 RCTs had high RoB; the remaining four had uncertain RoB in several domains of assessment. For three trials with uncertain RoB and without overt vested interest, it was inconclusive whether homeopathy combined with conventional intervention was more or was less effective than conventional intervention alone for modulation of immune response in calves, or in the prophylaxis of cattle tick or of diarrhoea in piglets.ConclusionDue to the poor reliability of their data, OTP-controlled trials do not currently provide useful insight into the effectiveness of homeopathy in animals.