Physicochemical Investigations of Homeopathic Preparations: A Systematic Review and Bibliometric Analysis—Part 1

Abstract

Objectives: The last systematic review of physicochemical research performed on homeopathic preparations was published in 2003. The aim of the study is to update and expand the current state of knowledge in the area of physicochemical properties of homeopathic preparations. In part 1 of the study, we aim to present an overview of the literature with respect to publication quality and methods used. In part 2, we aim to identify the most interesting experimental techniques. With this, we aim to be in a position to generate meaningful hypotheses regarding a possible mode of action of homeopathic preparations.Methods: A two-step procedure was adopted: (1) an extensive literature search, followed by a bibliometric and quality analysis on the level of publications and (2) a thorough qualitative analysis of the individual physicochemical investigations found. In this publication, we report on step (1). We searched major scientific databases to find publications reporting physicochemical investigations of homeopathy from its origin to the end of 2015. Publications were assessed using a scoring scheme, the Manuscript Information Score (MIS). Information regarding country of origin of the research and experimental techniques used was extracted.Results: We identified 183 publications (compared to 44 in the last review), 122 of which had an MIS ≥5. The rate of publication in the field was ∼2 per year from the 1970s until 2000. Afterward, it increased to over 5.5 publications per year. The quality of publications was seen to increase sharply from 2000 onward, whereas before 2000, only 12 (13%) publications were rated as “high quality” (MIS ≥7.5); 44 (48%) publications were rated as “high quality” from 2000 onward. Countries with most publications were Germany (n = 42, 23%), France (n = 29, 16%), India (n = 27, 15%), and Italy (n = 26, 14%). Techniques most frequently used were electrical impedance (26%), analytical methods (20%), spectroscopy (20%), and nuclear magnetic resonance (19%).Conclusions: Physicochemical research into homeopathic preparations is increasing both in terms of quantity and quality of the publications.

Homöopathie – Stand der Forschung

“…Die experimentelle Laborforschung zur Homöopathie prüft daher einerseits, ob empirische Evidenz für einen Unterschied zwischen Homöopathika und Lösungsmittel beobachtbar ist. Hierbei kommen physiko-chemische Testverfahren [20], wie Kernspinresonanzmessungen [21], pflanzliche Bioassays oder auch Tiermodelle zum Einsatz. Andererseits versuchen homöopathische Grundlagenforscher das Wirkprinzip von Hochpotenzen durch entsprechende Theoriebildung in naturwissenschaftlichen Kategorien verstehbar zu machen.…”

“…Keines davon konnte aber in allen unabhängigen Wiederholungsversuchen dieselben Resultate hervorbringen [34]. Zudem sind die gemessenen Effekte nicht selten so klein oder streuen derart stark, dass sie hart an der "Rauschgrenze" der verwendeten Testsysteme liegen [35,36]. Insgesamt bleibt festzuhalten, dass es auch in der präklinischen Forschung zur Homöopathie zu viele "positive" Befunde gibt, um sie ohne Weiteres durch die Placebohypothese zu erklären.…”

Interaction between Solvatochromic Dyes and Water Sampled from a Natural Source Treated with High Dilutions of Phosphorus

“…Recently, studies focusing on the physical properties of highly diluted substances have appeared in the scientific literature, leading to discussions concerning putative mechanisms of action. [12][13][14] Among the different experimental models currently being examined, we highlight the method developed by Cartwright, [15][16][17][18] in which the dipole-modulating activity of homeopathic dilutions can be demonstrated through their interaction with solvatochromic dyes. Changes in the spectra of these dyes can be shown to be a function of changes in solute and/or solvent polarity induced by ultrahigh dilutions.…”

Individualized Homeopathy for Depression in Climacteric Women: Comments on the Retraction by PLoS ONE

“…However, to enable a better understanding of this point by the PLoS ONE editors, we provided them with a body of contemporary evidence published in peer-review journals demonstrating biological effects of homeopathic preparations in cell, animal, and plant models. [10][11][12][13][14][15][16][17][18][19][20][21][22] Homeopathic medicines prepared to 30c and 200c are not simply diluted to 10 À60 and 10 À400 respectively: if they were, then indeed one would expect them to be inert. But the homeopathic manufacturing process involves succussion (vigorous shaking with impact) between each step of serial dilution.…”