Patients groups have complained of slippage on the NHS's evaluation of complaints project - ordered in November 1998.
Changes in personnel at the London Health Economics Consortium, York Health Economics Consortium and the Kings Fund have left the project in the hands of Dr John Posnet, formerly of York Health Economics Consortium.
The project - which was due to produce an interim report this month - has held just one meeting of an expert advisory group headed by East Sussex, Brighton and Hove health authority chief executive Alan Bedford.
One member of the group told HSJ that work presented so far was not as good as it could have been and lacked any real level of patient involvement .
The Department of Health, Dr Posnet and Mr Bedford were not available for comment.