NHS patients will be allowed to see and edit their medical records under proposals in a government-commissioned report.

The plan is contained in a report that an expert advisory group, headed by Professor Steve Field, the coalition's NHS troubleshooter, is finalising before handing it to the Department of Health.

The changes would enable patients to view their whole medical history, study the result of diagnostic tests and see what drugs they have been prescribed before. They would also be able to check on their next appointment and order a repeat prescription.

The NHS Future Forum will outline the significant extension of patients' rights in a report on how greater availability of information in the health service can improve treatment and make users of NHS services feel more involved and empowered.

The plan will help the health secretary, Andrew Lansley, finally realise his longstanding goal of an "information revolution" intended to help put patients more in control of their own care.

The scheme could be operational in England inside three years, the forum believes.

One forum member said that in an age when citizens could access their bank account details from their home computer, it was "unsustainable" for existing restrictions on patients' access to their medical records to continue.

Currently, patients' right to see their records is protected under the NHS Constitution but they have to apply for access and explain why they want to see them.

Although the recommendations are not binding on the government, Lord Howe, the health minister in the House of Lords, has already welcomed that plan. "We fully support patients having online access to their personal GP records. Our vision for a modern NHS is to give patients more information and control over their health," he told today's Times.

Patient groups are also likely to back the plan. "Many patients phone our helpline saying that they are having difficulty accessing their medical records from their GP, even though the NHS Constitution states that they have a legal right to do this," said Katherine Murphy, chief executive of the Patients Association.

But, in a sign that not everyone involved may welcome the change, Murphy added that patient confidentiality was crucial.

"Health records are among the most personal and sensitive information kept about patients and they must be protected. There must be a guarantee that all patient data will be protected and that it will not be possible to trace back information to an individual", she said.

Family doctors' attitudes to the plan will be vital. GPs may not back the idea of patients having such access, which could see them allowed to suggest corrections. But the forum's report will highlight the positive effect on doctor-patient relations of introducing such a scheme..