As many as 10 trusts have volunteered to be inspected by the Commission for Health Improvement when it starts work in April.

CHI plans to review 25 trusts in its first year, but it has a demanding target of inspecting every hospital and primary care group in England and Wales within four years.

Director Dr Peter Homa said: 'We are keen to make sure in the first year that we visit a cross- section of the NHS.

'We have had a number of trusts and primary care groups come forward and offer themselves as sites for some of the first visits, and are keen to help us develop our methods.'

King's Healthcare trust in London is among the first to volunteer. Chief executive Ron De Witt said the trust wanted to be 'a development site'.

Exeter PCG is also considering joining the first wave.

Former clinical governance lead Dr Kieran Sweeney - an adviser to CHI - said: 'There is always benefit from evaluation.'

Dr Homa said up to 10 organistions had already volunteered, a 'combination' of 'good, bad, keen, those who have had problems'. The 10 included primary care groups and mental health as well as acute trusts.

But patient watchdogs were surprised that CHI had agreed to visit trusts which volunteered for the process as a priority.

Elizabeth Manero, chair of the London Health Link umbrella organisation for community health councils, said: 'If the criterion for a CHI investigation is going to be the first people to put their hands up, that will defeat the object.

'We would like CHI to work on issues like the care of the elderly, not help with development work at trusts.'

She added: 'If they are casting about for where to start, I am quite willing to find some trusts in London where there is a problem.'

London Health Emergency campaigns director Geoff Martin was less surprised that King's had volunteered.

'They are the golden boys, the flagship, ' he said. 'London region thinks they are fantastic and they are favoured at the expense of other hospitals.'

Malcolm Alexander, chief officer of Southwark community health council, which covers King's, said he was surprised it had volunteered when it had some 'key' problems, including long waits in some specialties.

'I suppose they feel they have transformed a dodgy hospital into something respectable, ' he said.

Mr De Witt - who is also chair of the English National Board, which regulates nurse education - said he wanted to 'influence the process'.

'We won't get off lightly if we are working this through with them. Their interpretation will be that we have had advance warning, then when they come in to inspect us we should have it exactly right.'

Dr Sweeney, a member of CHI's clinical governance team, said it could help his PCG improve. 'Clinical governance has been embraced with substantial enthusiasm here.

'We think things are going OK but there is huge room for development.'

Ministers have given CHI a£7m budget and ordered it to tackle cancer services - in a joint inquiry with the Audit Commission - and clinical governance in its first year.