The NHS constitution is failing to attract public interest amid criticism that it is unclear about patients' rights and will not abolish the postcode lottery.

NHS organisations have struggled to get responses from the public to a consultation on the constitution that ended last Friday.

The Department of Health claimed the constitution would empower and engage the public when it announced the plans in June. But NHS Confederation primary care network director David Stout said: "PCTs haven't found it drives citizens to question things or have a debate. There are areas where there hasn't been much interest. In some there has been no response."

Many responses were on technical points, he said, rather than on the "fairly uncontroversial" principles enshrined in the constitution. He admitted it had not been top of PCTs' lists of priorities.

The NHS Confederation's response calls for clarity on to whom "patients' rights" applied.

NICE ideas

The right to drugs and treatments recommended by the National Institute for Health and Clinical Excellence may create a "false expectation" among patients as it does not refer to funding availability, it says. As NICE will not appraise all drugs, PCTs will have to set priorities and local variations will continue.

More detail is needed on how the NHS will implement the constitution, the confederation says.

It also wants any further values and staff pledges to be developed from the bottom up, saying: "Organisations already have their own values and identity. It is important the statements in the constitution do not undermine these established values and identities or cause confusion."

However, Unison is calling for the staff rights to go further, saying they cover only basic minimum rights even though NHS staff already enjoy working conditions that exceed legal entitlements.

The DH was unable to say how many consultation responses it had received from PCTs and other NHS organisations.