A study backed by the NHS Commissioning Board (NHSCB) has found that the sharing of publicly-available prescribing data could save the NHS in England millions of pounds a year.

Concentrating on statins, the researchers worked with publicly-available NHS prescription data to analyse the prescribing patterns of GP practices, clinical commissioning groups (CCGs) and Primary Care Trusts (PCTs) over an eight-week period, to discover how much money was spent in each area on the more expensive drugs in the class. 

Its findings estimate that in 2011, NHS England had an average £27 million a month of "potentially unnecessary" expenditure on two brand-name statins, and that, if the research had been conducted the previous year, over £200 million could have been saved in this class alone.

The NHSCB-backed research was conducted by Mastodon C - a big-data start-up company based at The Open Data Institute (ODI), Open Health Care UK - the health technology start-up behind the NHS Hack Days, and Ben Goldacre, the doctor and writer behind BadScience.net.

The researchers say that the potentially unnecessary expenditure on brand-name statins which they have discovered "is part of a wider issue of spending on propriety drugs in cases where good and far cheaper generic equivalents exist." Previous research has estimated that these wider patterns cost the NHS over £1 billion a year in excess spend, they add.

The cost of an individual prescription item can vary from as little as 81p for a generic to over £20 for drugs still under license to the pharmaceutical companies that develop them, they say.

However, the researchers also point that the set of available drugs is constantly evolving and that the right prescription for each individual is "very personal."

"We cannot say that the prescribing costs identified here are 'waste,' but a clear public overview of the data can make it easier for doctors, patients, politicians, the NHS and the public to identify potential savings," they say.

The initial data analysis is available through Prescribing Analytics, a new online portal which is open to all, and should be "required reading" for all GPs as they seek to make the best use of their resources, said ODI chairman Nigel Shadbolt.

"In using open data to highlight trends, we see where we can do better and make improvements. Inefficiency in any system often results from poor or incomplete information about the overall picture. This is something that open data can address, as Prescribing Analytics so dramatically illustrates," said Mr Shadbolt.

"We've suspected for some time that there were potential savings to be gained by looking at prescribing practices across the NHS, but I wasn't prepared for the extent of the potential savings we've seen in just this analysis," added Mastodon C's Francine Bennett, who carried out the data analysis.

"What's important now is to work with the NHS and healthcare professionals to provide the data and analysis that can realise this potential," said Ms Bennett.

Dr Goldacre pointed out that this project, which had cost "almost nothing to build," had found potentially huge savings for the NHS, while Carl Reynolds, co-founder of Open Health Care UK, added that not only does the project illustrate significant potential savings in the NHS drugs budget, it also shows how open data can facilitate mass collaboration "with impressive results."

NHSCB medical director Sir Bruce Keogh welcomed the study findings, pointing out that variation in prescribing habits costs the NHS millions of pounds a year.

'Transparent sharing of information will help clinicians understand whether they are over- or under-prescribing. This will focus minds in a way that will not only improve the quality of treatment for patients but also reduce cost and free up money for re-investment in other parts of the NHS," said Sir Bruce.

The team working on Prescribing Analytics say that they have identified several more drug categories that they plan to analyse.