There is a general perception that online medical journals have a smaller carbon footprint than its printed version. The financial cost itself follows a similar argument. From this, it can be expected that the subscription rates for online and print versions of medical journals would portray the perceived impression. This is in fact so, for leading journals such as the BMJ, Lancet, New England Journal of Medicine, JAMA, Medical Journal of Australia. The British Journal of Surgery on the other hand has the same subscription rates for online and print versions for both the UK and international subscribers. It is not known if this is due to actual costs or due to business reasons. It also not unusual for surgeons to act differently!
Coming back to the perception that online journals are greener, it is imperative to find the evidence. Reliable high level evidence in the best traditions of medical research is hard to come by with regard to the carbon footprint of print products and downloading journal articles. One research paper from Finland (http://www.vtt.fi/inf/pdf/tiedotteet/2010/T2560.pdf) indicated 253g of carbon emissions for a 170g -56 page magazine. However the paper goes on to describe different scenarios with different emission numbers which make application of such data on a medical journal difficult.
A research paper by Weber, Koomey and Matthews which compared different scenarios of music CD vs. download (http://gdi.ce.cmu.edu/docs/the-energy.pdf ) indicated the carbon emission of downloading a music album at 400g. However this figure would be expected to change if the web browsing time, size of the downloaded file and the graphic content are altered. The file size of a music album is much larger than a usual medical journal.
While the background conditions of the two quoted papers are not comparable, it brings in to focus the need for good evidence and comparable base conditions. It may be akin to comparing the proverbial apples and oranges. I would be delighted to hear more views and facts from other members of this forum. It may be opportune for this forum to consolidate the evidence of the carbon footprint of print vs. online medical journals.