The tobacco industry has been shown to mislead with its research, but is forcing it to become more hidden a better option?

Last week, the BMJ announced that it was finally implementing a practice that it had been discussing since the mid 1990s. Research partly or fully funded by the tobacco industry will no longer be published in BMJ, BMJ Open, Thorax and Heart.

This brings the journal in line with its own Tobacco Control journal, as well as a number of other publications, including PLoS Medicine, PLoS One, PLoS Biology and the Journal of Health Psychology.

It's a turnaround for the BMJ, who published an editorial criticising the American Thoracic Society when it brought in the policy in 1996. It started a debate at the time, and since then, more and more evidence has shown that the tobacco industry has deliberately skewed scientific knowledge by presenting findings in a misleading way, withholding certain findings, and promoting false evidence of doubt in the scientific consensus about the harms of tobacco.

Not only that, internal documents have revealed this practice is still very much alive today, with memos earlier this year coming to light detailing a campaign to "ensure that PP (plain, or standardised packaging) is not adopted in the UK".

While a lot of public health researchers are delighted by this news, even feeling that the BMJ are late to the game in implementing these restrictions, some are more worried by this censorship. Consider electronic cigarettes as an example. Nicoventures is in the process of developing the first MHRA-approved approximation of an e-cigarette (its device is not technically an e-cigarette, but is similar).

The company is running trials on the product at the moment. But though Nicoventures is a stand-alone company, it is owned by British American Tobacco. Under these new rules, it will not be able to publish its results in any of these journals.

At the moment e-cigarettes are unregulated, so current knowledge of their potential harms and benefits, is based on anecdote and speculation rather than data. As tobacco companies buy up e-cigarettes companies, this will make researching their efficacy as a nicotine replacement therapy difficult or potentially even impossible. Already there are plans to regulate them as a medical product, which may mean they could be removed from sale until they had been properly tested.

I personally believe this would be a poor decision; although we are unsure of the long-term harms resulting from the use of these devices, it's practically inconceivable that they will be more harmful than smoking cigarettes, and will likely be considerably less so. Given the tales of hardened smokers finding them an effective replacement for cigarettes, removing them from the market may well result in a lot of people going back to smoking, which would be a negative outcome.

Finally, as we already know from the work of people like Ben Goldacre, a big problem in medical literature is the selective withholding of data by those with vested interests. Not just the tobacco industry, but the pharmaceutical industry as well.

Goldacre calls for regulations that would force all this unpublished data to be made public, rather than for banning pharma from funding research. Perhaps it's a slightly different issue, since pharma are creating products to cure, whereas the tobacco industry creates a product that kills. But ultimately, both are businesses, primarily concerned with making money.

Might banning the tobacco industry from funding work to be published in these journals lead to it adopting worse practices, and actively obscuring its role in funding research? At the moment, declaration of financial support is essentially an honour system. There's not really anything beyond integrity stopping a researcher from simply not disclosing who funded research. If tobacco companies deliberately obscure their involvement with research, we would be in an even worse situation, where we as scientists would not know if research had a higher chance of bias due to the involvement of the tobacco industry.