Well designed experiments should have been used

EDITOR—The publication of a paper by Schapowal and the Petasites Group, purporting to show that butterbur is as good as antihistamines for hay fever and is without their alleged disadvantages, has done the disease and those suffering from it a disservice.1 The primary concern of the paper was not the effect of these treatments on the severity of hay fever. To establish this, the essential data are the severity of sneezing, rhinorrhoea, itchy nose and eyes, and nasal congestion before and after treatment. These were given only as diagnostic entrance criteria, and severity of disease became just a secondary outcome measure, derived not from measurement of change in disease state, but from a final, global, clinicians' assessment.

The primary outcome measure was not an objective assessment of the disease state but a mishmash of various attributes of mental, physical, and social activity—all secondary consequences of the disease. Since the antihistamine produced the drowsiness and fatigue, as expected by Schapowal et al, in two thirds of those taking it, this would inevitably have had an adverse effect on the physical, psychological, and social wellbeing detected by their primary outcome measure. Thus the spurious primary effect measured is likely to have been an unwanted effect of the drug, totally unrelated to any change in the state of the disease.

This study has absolutely no bearing on the relative therapeutic potency of butterbur …