Homeopathy for the common cold: is this another case of scientific misconduct?

The common cold is one of the indications for which homeopathy is deemed to be effective… by homeopaths that is! Non-homeopaths are understandably critical about this claim, not least because there is no good evidence for it. But, hold on, there is a new study which might change all this.

This study was recently published in COMPLEMENTARY THERAPIES IN MEDICINE which is supposed to be one of the better journals in this area. According to its authors, it was conducted “to determine if a homeopathic syrup was effective in treating cold symptoms in preschool children.” Children diagnosed with an upper respiratory tract infection were randomized to receive a commercial homeopathic cold syrup containing allium cepa 6X, hepar sulf calc 12X, natrum muriaticum 6X, phosphorous 12X, pulsatilla 6X, sulphur 12X, and hydrastasis 6X or placebo. Parents administered the study medication as needed for 3 days. The primary outcome was change in symptoms one hour after each dose. Parents also assessed the severity of each of the symptoms of runny nose, cough, congestion and sneezing at baseline and twice daily for 3 days, using a 4-point rating scale. A composite cold score was calculated by combining the values for each of the four symptoms. Among 261 eligible participants, data on 957 doses of study medication in 154 children were analyzed. There was no significant difference in improvement one hour after the dose for any symptom between the two groups. Analysis of twice daily data on the severity of cold symptoms compared to baseline values found that improvements in sneezing, cough and the composite cold score were significantly greater at both the first and second assessments among those receiving the cold syrup compared to placebo recipients.

The authors concluded that the homeopathic syrup appeared to be effective in reducing the severity of cold symptoms in the first day after beginning treatment.

Where to start? There are so many problems with this study that I find it difficult to chose the most crucial ones:

• The study had a clearly defined primary endpoint; it was not affected by the homeopathic treatment which doubtlessly makes the study a negative trial. The only correct conclusion therefore is that THE HOMEOPATHIC SYRUP FAILED TO AFFECT THE PRIMARY OUTCOME MEASURE OF THIS STUDY. THEREFORE THE TRIAL DID NOT PRODUCE ANY EVIDENCE TO ASSUME THAT THE EXPERIMENTAL TREATMENT WAS EFFICACIOUS.
• I don’t think that many of the primary or secondary outcome measures are validated or reliable.
• All the positive results reported in the abstract and the article relate to secondary endpoints which are purely explanatory by nature. They should, in my view, not be mentioned in the conclusions at all.
• The fact that some results turned out to be positive can be explained by the fact that the investigators ran dozens of tests for statistical significance which means that, by simple chance, some will turn out to produce a positive result.
• A further explanation for the seemingly positive results might be the fact disclosed in the text of the article that the children in the homeopathy group received more conventional drugs than those in the placebo group.
• Whatever the reason for these positive results, they certainly had nothing to do with the homeopathic syrup.
• The study was funded by the company producing the syrup and for which one of the authors was employed as a consultant. This might be an explanation for the abominably poor science. In other words, this paper is not an exercise in testing a hypothesis but one in marketing.

While I might forgive the company for trying to maximise their sales figures, I do find it harder to forgive the authors, reviewers and editors for publishing such overtly false conclusions. In my view, they are all guilty of scientific misconduct.