By accepting only advertisements for drugs and medical devices, medical journals have accepted an exclusive and dependent relationship with pharmaceutical companies, claims a team of researchers in an investigation published in PLoS Medicine.

In a study of the nine top multi-specialty medical journals – based on advertising revenues – the researchers found that in eight advertisements were almost exclusively for drug products, rather than other products which may be of interest to doctors.

According to Adriane Fugh-Berman and colleagues of Georgetown University School, the analysis showed that among advertisements in the Journal of the American Medical Association (JAMA), for example, 99% (211 out of 214) in 2004 were for pharmaceuticals.

“By exclusively featuring advertisements for drugs and devices, medical journals implicitly endorse corporate promotion of the most profitable drugs. Advertisements and other financial arrangements with pharmaceutical companies compromise the objectivity of journals.”

Drug companies place a high value on advertising in medical journals, say Fugh-Berman and colleagues, because research has shown that such advertising increases prescriptions for targeted drugs in a dose-related manner. Drug companies get a huge return on investment (ROI) from these adverts - one study found that the ROI (the average increase in revenues per incremental dollar spent in any given month) was $5.

Fugh-Berman and colleagues wanted to understand why these journals exclude other types of advertisements, and hypothesised that perhaps it was only drug companies that could afford to buy journal advertising space. In fact, their investigation found that medical journal advertisements are cheaper than those in consumer magazines, and medical journals sometimes emphasise their cheap advertisement rates when reaching out to drug companies.

Medical journals, say the authors, sometimes argue that drug advertisements provide doctors with valuable information about drugs and diseases. Not so, claim the authors.

“If medical journals accepted only advertisements for drugs proven superior in comparative trials,” they say, “the argument that drug advertisements are educational could be rationalised. No journal, however, requires demonstration of product superiority as a condition for advertising.”

The scholarly nature of journals confers credibility on both articles and advertisements within their pages, claim Fugh-Berman and colleagues.

The authors argue that the time has come for medical journals to eschew drug advertisements altogether and find sources of revenue that are less compromising.

“Why not run ads for cars, computers or other consumer products that doctors would buy for themselves?” says Fugh-Berman, who also pointed out that pharmaceutical adverts in journals are third-party adverts - a doctor whose prescribing is swayed by a drug advert isn’t paying for the product advertised.

PLoS Medicine does not accept advertising from drug companies.