At least this is what the authors of this new study want us to believe.
But are they right?
This RCT is entitled ‘Efficacy and tolerability of a complex homeopathic drug in children suffering from dry cough-A double-blind, placebo- controlled, clinical trial’. It recruited children suffering from acute dry cough to assess the efficacy and tolerability of a complex homeopathic remedy in liquid form (Drosera, Coccus cacti, Cuprum Sulfuricum, Ipecacuanha = Monapax syrup, short: verum).
The authors stated that “preparations of Drosera, Coccus cacti, Cuprum sulfuricum, and Ipecacuanha are well-known antitussives in homeopathic medicine. Each of them is connected with special subtypes of cough. Drosera is intended for inflammations of the respiratory tract, especially for whooping cough. Coccus cacti is intended for inflammations of the nasopharyngeal space and the respiratory tract. Cuprum sulfuricum is intended for spasmodic coughing at night. Ipecacuanha is intended for bronchitis, bronchial asthma, and whooping cough. The complex homeopathic drug explored in this trial consists of all four of these active substances.”
According to the authors of the paper, “the primary objective of the trial was to demonstrate the superiority of verum compared to the placebo”.
A total of 89 children, enrolled in the Ukraine between 15/04/2008 and 26/05/2008 in 9 trial centres, received verum and 91 received placebo daily for 7 days (age groups 0.5–3, 4–7 and 8–12 years). The trial was conducted using an adaptive 3-stage group sequential design with possible sample size adjustments after the two planned interim analyses. The inverse normal method of combining the p-values from all three stages was used for confirmatory hypothesis testing at the interim analyses as well as at the final analysis. The primary efficacy variable was the improvement of the Cough Assessment Score. Tolerability and compliance were also assessed. A confirmatory statistical analysis was performed for the primary efficacy variable and a descriptive analysis for the secondary parameters.
A total of 180 patients (89 in the verum and 91 in the placebo group) evaluable according to the intention-to-treat principle were included in the trial. The Cough Assessment Score showed an improvement of 5.2 ± 2.6 points for children treated with verum and 3.2 ± 2.6 points in the placebo group (p < 0.0001). The difference of the least square means of the improvements was 1.9 ± 0.4. The effect size of Cohen´s d was d = 0.77. In all secondary parameters the patients in the verum group showed higher rates of improvement and remission than those in the placebo group. In 15 patients (verum: n = 6; placebo: n = 9) 18 adverse drug reactions of mild or moderate intensity were observed.
The authors concluded that the administering verum resulted in a statistically significantly greater improvement of the Cough Assessment Score than the placebo. The tolerability was good and not inferior to that of the placebo.
This study seems fairly rigorous. What is more, it has been published in a mainstream journal of reasonably high standing. So, how can its results be positive? We all know that homeopathy does not work, don’t we?
Are we perhaps mistaken?
Are highly diluted homeopathic remedies effective after all?
I don’t think so.
Let me explain to you a few points that raise my suspicions about this study:
- It was conducted 10 years ago; why did it take that long to get it published?
- I don’t think highly of a study with “the primary objective … to demonstrate the superiority” of the experimental interventions. Scientists use RCTs for testing efficacy and pseudo-scientist use it for demonstrating it, I think.
- The study was conducted in the Ukraine in 9 centres, yet no Ukrainian is an author of the paper, and there is not even an acknowledgement of these primary investigators.
- The ‘adaptive 3-stage group sequential design with possible sample size adjustments’ sounds very odd to me, but I may be wrong; I am not a statistician.
- We learn that 180 patients were evaluated, but not how many were entered into the trial?
- The Cough Assessment Score is not a validated outcome measure.
- Was the verum distinguishable from the placebo? It would be easy to test whether the patients/parents were truly blinded. Yet no such results were included.
- The trial was funded by the manufacturer of the homeopathic remedy.
- The paper has three authors 1)Hans W. Voß has no conflict of interest to declare. 2) Rainer Brünjes is employed at Cassella-med, the marketing authorisation holder of the study product. 3) Andreas Michalsen has consulted for Cassella-med and participated in advisory boards.
I know, homeopathy fans will think I am nit-picking; and perhaps they are correct. So, let me tell you why I really do strongly reject the notion that this study shows or even suggests that highly diluted homeopathic remedies are more than placebos.
The remedy used in this study is composed of Drosera 0,02 g, Hedera helix Ø 0,04 g, China D1 0,02 g, Coccus cacti D1 0,04 g, Cuprum sulfuricum D4 2,0 g, Ipecacuanha D4 2,0 g, Hyoscyamus D4 2,0 g.
In case you don’t know what ‘Ø’ stands for (I don’t blame you, hardly anyone outside the world of homeopathy does), it signifies a ‘mother tincture’, i. e. an undiluted herbal extract; and ‘D1’ signifies diluted 1:10. This means that the remedy may be homeopathic from a regulatory point of view, but for all intents and purposes it is a herbal medicine. It contains an uncounted amount of active compounds, and it is therefore hardly surprising that it might have pharmacological effects. In turn, this means that this trial does by no means overturn the fact that highly diluted homeopathic remedies are pure placebos.
It’s a pity, I find, that the authors of the paper fail to explain this simple fact in full detail – might one think that they intentionally aimed at misleading us?