NOT enough people are aware of a new NHS data sharing programme, a health watchdog has warned.

From April people’s medical histories with their GPs will be shared with researchers and pharmaceutical companies on a database unless they ask to be excluded.

It is argued the mass storage of the data – which will be “anonymised” – will benefit medical science by helping researchers understand causes of disease, outbreaks of infection and see drug side effects.

But Healthwatch York has raised concerns that leaflets being sent to every household, intended to inform people they can opt out, are being mistaken as advertising flyers and thrown away.

Questions have also been raised about which “approved health care organisations” the data may be shared with.

Sian Balsom, manager at Healthwatch York, said the leaflet did not tell people that if they want to opt out they should contact their GP, or make it clear that data can be shared with private companies.

“Although they say any identifiers are removed, there are concerns about how easy it can be with postcode data and some basic health information to identify actual individuals.

“People need to understand there’s a choice. There are people who are very keen on this, it’s not all a negative picture but there’s not enough information about how this will look and how we stop misuse of this.”

The Government’s Health and Social Care Information Centre will collect information from places such as GP practices and hospitals.

All information available to the public will be anonymous. Other data will be “pseudo-anonymised” before being released to “approved organisations” – meaning that it would be difficult but in some cases not impossible to identify the individual. Information that identifies people can only be disclosed with their explicit consent.

An NHS England, North Yorkshire and Humber spokesman said the programme was supported by a nationwide marketing campaign including posters and leaflets to GP surgeries, collaborations with patient and voluntary groups and charities to maximise awareness, and an online and social media campaign.

"We are also keen to ensure that patients are able to raise any concerns they may have about the sharing of their information, including their wish to opt out of the scheme if they wish, and we would encourage patients to discuss this with their GP practice.”

For details phone 0300 456 3531 or visit www.nhs.uk/caredata