Under guidance for the patient participation DES that takes effect from this financial year, practices must prove they have built patient representative groups that reflect the age, sex and ethnicity of their practice populations.
But Derbyshire LMC secretary Dr John Grenville said: 'We have a lot of groups in Derbyshire. But they are made up of those who can be bothered to get involved. They are dominated by elderly retired people with the time to take part.'
He said some practices would have to work far harder than others to shape representative groups.
The groups will effectively have a veto on major changes to services practices provide.
Dr Grenville said there was a concern practices that wanted to drop out of extended hours because funding for it had been reduced could find their patient group blocked the move.
'If the patient group says no, you would have to discuss dropping something else,' Dr Grenville said.