Doctors generally claim that their main source of information about pharmaceuticals is peer-reviewed publication of clinical trials. However, research shows that this is one of their least-used sources.

Accurate information about doctors’ sources of information can be obtained by asking them questions about drugs with a particularly dramatic difference between published science and marketing materials. Their responses reveal that they often obtain their information from drug company materials.

A recent report in the journal Family Practice concluded for new drugs “The most important sources were the pharmaceutical industry [49 percent], in particular the company representative, non-peer-reviewed literature, the mass media, and, to a lesser extent, hospital colleagues. Peer-reviewed literature or independent drug information sources were rarely significant at this stage.”

Meetings with drug company salesmen and attending sponsored “educational” events or drug company symposia result in increased prescribing of the drugs promoted. The majority of attendees at all-expenses-paid symposia claimed that it would not alter their prescribing practices, yet afterwards they often doubled their usage of two drugs being promoted.

The habit of accepting financial benefits from pharmaceutical companies usually starts in medical schools that rarely regulate interactions between drug salesmen and residents. Graduates from McMaster University, where such a policy does exist, relied less on drug company information, than those from the University of Toronto, which had no restrictions.

Information from drug company representatives is biased towards pharmaceutical solutions to problems (as opposed to nutrition, exercise, or even doing nothing) and towards their own products. One study found that 11 per cent of statements were not only biased towards the representative’s drug company, but also false. Yet, when these false statements were made during a presentation to doctors and students at a teaching hospital, they went unchallenged.

Even when more conscientious physicians do read scientific literature on drugs, they are still subjected to bias. Drug companies often fund the research. Researchers, and the institutions they work for, may own related stocks or patents. Studies showing a new drug is no better or even worse than an old drug or placebo are less likely to get published, while research friendly to drug companies may be published several times, with the author list scrambled to make it less obvious. These biases mean the results are more likely to be favourable to new drug therapies.

Drug companies spend $1 billion annually on marketing. Almost half goes to sales representatives who work with physicians–$10,000 for each Canadian doctor. Pharmaceutical Marketing magazine says identifying opinion leaders, building successful relationships with them, and training sales staff to communicate “effectively” are paramount.

The current system evolved because drug companies want increased sales. Doctors hold the legal right to prescribe pharmaceuticals. Patients are increasingly exposed to direct-to-consumer drug marketing, and often come into a doctor’s office with a brand name in mind. Patients trust the advice of their doctors. They do not realize that it often comes via pharmaceutical companies. Doctors use this source of information because it is associated with financial benefits, and is conveniently and attractively packaged.

The best action that people can take is to educate themselves from a variety of sources. Only by considering a spectrum of views will it be possible to determine the risks and benefits of each approach to a medical condition.

David Crowe is a Calgary-based environmentalist and analyst of the scientific justification for modern medicine. He has an HBSc in Biology and Mathematics. He can be reached at David.Crowe@aras.ab.ca.

Source: alive #252, October 2003