BMJ 2004;328:485 (28 February)

Only 6% of drug advertising material is supported by evidence

Heidelberg Annette Tuffs

A new study of the advertising material and marketing brochures sent out by drug companies to GPs in Germany has shown that about 94% of the information in them has no basis in scientific evidence.

The study, carried out by the Institute for Evidence-Based Medicine, a private independent research institute in Cologne, evaluated 175 brochures containing information on 520 drugs, which were either sent by post or handed out to 43 GPs since last June. The study was published in this month’s issue of the drugs bulletin Arznei Telegramm (2004;35:21-3; www.di-em.de/data/at_2004_35_21.pdf ).

About 15% of the brochures did not contain any citations, while the citations listed in another 22% could not be found. In the remaining 63% the information was mostly correctly connected with the relevant research articles but did not reflect their results. Only 6% of the brochures contained statements that were scientifically supported by identifiable literature.

The evaluation was done by two specially trained and independently acting reviewers. In cases of doubt a third reviewer was involved.

"This is the first study in Germany evaluating the quality of drug advertising material," says Thomas Kaiser, a scientist at the institute who published the study together with Peter Sawicki and other colleagues.

He points out that the advertising material presents distorted images of the drugs’ profiles. The article lists several examples of misrepresentation: medical guidelines from scientific societies are misquoted or changed, the side effects of drugs are minimised, groups of patient are wrongly defined, study results are suppressed, treatment effects are exaggerated, risks are manipulated, and effects of drugs were drawn from animal studies.

The authors warn that such a high amount of misinformation puts patients’ health at risk. Studies from other countries have shown that doctors tend to base their decisions on the information and advertising material sent out by drug companies. Therefore, the authors conclude, an independent institution should be established to monitor the content of such material.

The German drug industry has decided to tighten the rules in its self regulatory code on relations between the industry and the medical profession with regard to cooperation in clinical studies and attendance at conferences that are funded by drug companies.

The German Association of Research Based Pharmaceutical Companies in Berlin announced that its members have set up an independent tribunal in Berlin. Members of the tribunal will be chosen by drug companies and doctors’ and patients’ groups but will not be elected representatives of those bodies. Like a court, the tribunal will be able to punish companies that break the rules, imposing fines of up to €50 000 (£34 000; $63 000) or, in the case of a second offence, up to €250 000. Anyone will be allowed to notify the tribunal of possible offences.

The initiative was the industry’s reaction to the German government’s threat to install an executive against corruption. Doctors’ associations have also tightened their rules on corruption.

More information about the Institute for Evidence-Based Medicine can be found on its website, www.di-em.de/z_index.htm