In 2011 research physician Tristan Barber responded to an editor’s choice on conflicts of interest, saying: “Reading the current BMJ and noting several letters regarding conflicts of interest, it was particularly distracting to have the front cover being a fold-out advertisement for a pharmaceutical product.

“As a consequence I was very aware of all of the pharmaceutical advertising throughout the current edition. This may have been commented on before, but whilst considering industry impact on researchers and authors, has there been much consideration of the impact of advertising within a journal on the opinion of readers on its editorial policy or contents?”

Dr Barber’s concerns sprang to mind last week when the BMJ’s editorial advisory board assembled in London for its annual meeting. The board consists of internationally renowned and active clinicians, clinical academics, and health policy experts.

As part of the meeting we discussed the journal’s Too Much Medicine campaign, which aims to highlight the threat to human health posed by overdiagnosis and the waste of resources on unnecessary care.

One board member asked how we square campaigns about overdiagnosis and overtreatment with a business model that relies on pharma advertising for new drugs. More specifically, if there was evidence that a drug fell into the category of too much medicine, would we still publish it? Does anybody at the BMJ vet them to ensure that a drug’s benefits aren’t over-stated?

Editor-in-chief Fiona Godlee compared the BMJ campaign and its advertising policies with The Guardian newspaper, which has a long-standing interest in highlighting climate change, but still publishes hefty travel supplements with advertisements for long haul travel.

BMJ Group believes that the sale of display advertising space is a legitimate source of revenue to support the publication of its journals in print and online. The BMJ’s advertising policy asks that ads are “legal, decent, and honest” and comply with the laws of the country in which they are to be seen.

Advertisers shoulder this responsibility, working within the regulatory codes of practice devised by bodies such as the ABPI  At the BMJ we often talk of the “Chinese wall,” a clear demarcation between the advertising sales and editorial teams. This safeguard helps to avoid conflicts of interest, and means advertisers have no prior knowledge of an article that may mention their product, either positively or negatively. You can read our advertising policy on the BMJ Group website  It’s quite complex and is currently being restructured to make it easier to navigate.

The policy has separate sections for some products, such as tobacco and food. Two years ago the BMJ was accused of running an ad that lent credence to a marketing campaign sponsored by bottled water manufacturer Danone on the Hydration for Health website.

Glasgow GP Margaret McCartney  led the charge on her blog before writing a follow-up BMJ feature  about the evidence to support the idea that we don’t drink enough water. The journal decided the ad had breached BMJ Group’s advertising policy about foodstuffs, which states: “Advertisement for foodstuffs, food supplements, vitamins, and minerals should conform to the guidelines of the British Code of Advertising and Sales Promotion and should be submitted with full substantiation of all claims.

“All claims must be referenced to full length research papers published in peer reviewed scientific journals. (Abstracts won’t do.)The BMJ editor must approve all advertisements before publication.”

If readers dislike an ad, they can follow McCartney’s example and complain to the journal, usually by submitting a response. The advertiser is then shown the response and asked to comment.

Why does any of this matter? Perhaps this is best explained not by the BMJ but by self-styled “grumpy scientist” Dr Aust, who responded to McCartney’s blog post about Hydration for Health’s ad on bmj.com: “Honestly, if the BMJ are going to let this kind of sh*te run on their site, what hope is there for the rest of us trying to counteract all the “Hydration balls” in the mainstream press etc?”

David Payne is editor, bmj.com, and readers’ editor.