Patients should have a right to anonymity should data accumulated by GPs be used for other purposes, the General Medical Council (GMC) says in a new directive.
GPs should also pressure PCTs to ensure IT systems that do not guarantee patient anonymity are updated or replaced to ensure that they do.
They must also ensure that patients are warned that accumulated data may be used for financial and administrative purposes, such as supplying information to the Quality and Outcomes Framework (QOF).
The guidance provided by the GMC suggests that doctors may disclose such data, but anonymity should whenever possible be maintained.
If it is not possible to maintain anonymity, then it is vital for patient consent to be sought. In addition, posters and leaflets should be made available to provide more information and explain how patients can lodge an objection.
GMC policy adviser Michael Keegan said that many PCTs like to check the accuracy of QOF data against practice records. But some practices still tell the GMC that their IT systems "don't allow names to be removed without receptionists whiting out names".
"The important thing is that patients are informed and realise they have a right to object," he said.