Almost two-thirds of people do not think patients have been well informed about the controversial NHS data scheme, a poll suggests.

Despite the fact that NHS England, which is behind the care.data programme, says it has sent leaflets about the initiative to every home in England, 65 per cent of people said the scheme had not been well-publicised to the public.

The initiative was pushed back until the autumn after patients, doctors and other professional organisations raised concerns that they had been given too little time to learn about the project.

A new survey by the Royal College of General Practitioners has found that 66 per cent of the 2,000 British adults polled did not think there was enough information available about people’s rights to opt out.

Despite the concerns, more people said they are in favour of the initiative than oppose it - 27 per cent said they are against the rollout of the programme, 34 per cent are in favour and 39 per cent are unsure.

RCGP honorary secretary Nigel Mathers said: “Far more needs to be done in order to make the case for care.data - and to explain to people about their right to opt out of having their data used.

“Unless the government works harder to explain why care.data is such a vital project and how it will be implemented, it will never enjoy the backing or confidence of the public or GPs.

“The government must dramatically step up its efforts to publicise the need for the database and the right of people to opt out, as a matter of urgency.”

NHS England has said it will work with patients and professional groups to promote awareness of the scheme.

Last week, health secretary Jeremy Hunt announced that he was going to introduce new legislation which meant that insurance companies could not buy data through the scheme.

Mr Hunt wanted to provide “rock-solid” assurance to patients that confidential information will not be sold for commercial insurance purposes, the Department of Health said.

The idea behind the care.data programme is to link data from GP records with information from hospitals to give an idea of what happens to patients at all stages of the NHS.

The data that will be extracted from GP systems includes information on family history, vaccinations, referrals for treatment, diagnoses and information about prescriptions. It will also include biological values such as a patient’s blood pressure, body mass index and cholesterol levels.

Personal confidential data will also be taken, such as date of birth, postcode, NHS number and gender. The written notes a GP makes during a consultation will not be extracted.

The data will be held by the Health and Social Care Information Centre and anonymised by officials there. Fully anonymised data will be made available publicly to anyone outside the NHS.

Data considered to be potentially identifiable - for example where a patient in a small town has a rare disease - will only be released to approved organisations for the specific purpose of benefiting the health and social care system.