Plymouth Hospitals trust chief executive Arthur Wilson has resigned following an investigation into the management of waiting list figures which found 'irregularities' and 'unacceptable practice'.

Mr Wilson's departure, and publication of the inquiry's report, followed claims that the trust had manipulated lists, and a subsequent Department of Health audit which found that 90 patients who had been waiting more than 18 months for surgery were missing from the waiting lists.

In his resignation letter Mr Wilson accepted there had been 'a breakdown of confidence' between himself and the trust. Deputy chief executive Martin Cusack resigned earlier this month .

The report, by Chelsea and Westminster trust chief executive Heather Lawrence, blames a lack of central management and monitoring of waiting lists, and inadequate data management. It also presents evidence that waiting lists were deliberately altered.

Patients waiting longer than 18 months were not reported, and the dates they were placed on a list were altered to circumvent shortfalls in the computer system, or to hide those waiting 18 months.

Patients were inappropriately placed on lists used to keep track of patients temporarily unavailable for treatment.

'Good practice would be that 5 per cent of patients were on suspended waiting lists at any one time. This trust's total of 22 per cent was clearly unusually high, ' says the report.

When the trust failed to meet targets set by Cornwall and Isles of Scilly health authority, the figures were adjusted to make it look as though the targets had been met.

The trust has accepted the report's recommendations, which include restructuring the management team and involving clinicians in the management of waiting lists.