Former Health and Disability Commissioner Ron Paterson wants changes to the makeup of the Medical Council of New Zealand, saying there is a cosiness between the council and the medical profession.

In a book titled The Good Doctor to be published next week, Professor Paterson says as many as 200 doctors are incompetent and the council's methods of identifying them are weak.

The professor of health law and policy at Auckland University was New Zealand Health and Disability Commissioner between 2000 and 2010.

He wants the council's membership changed from the current ratio of eight doctors and four lay people to equal representation of doctors and lay people, Fairfax reports.

Medical groups are rejecting his suggestions, arguing the council provides high levels of professional insight.