One person has been suspended since the internal review into the administrative management of a patient waiting list began.

However, Peterborough and Stamford Hospitals NHS Foundation Trust has stressed it is purely a record-keeping "anomaly" and no patients have been adversely affected.

The hospital has stressed that the member of staff was not suspended as part of any disciplinary action, but as a "neutral act" to help the investigation.

However, the incident is an embarrassing one following the revelation last January of an orthopaedic waiting list fiddle which resulted in new chief executive Nik Patten marking his arrival at the trust by making an unreserved public apology.

The probe was officially launched last week following the discovery of an error with an outpatient booking process — for elective, or non-emergency, appointments.

The foundation trust regulator, Monitor, has been informed.

The review is still underway, but the mistake is believed to have affected the treatment records of about 5,700 patients.

Apparently, the error would show on the computer system that a patient who had been treated within seven weeks had been treated within five. But this did not affect the hospital hitting Government targets, it has been stressed.

It has been emphasised that no patients will have to wait, or have had to wait any longer, for treatment as a result.

Two-thirds of the patients have already been seen and the matter concerns only the administrative process for this waiting list. The trust expects the investigation to be completed within the next few weeks.

Mr Patten said systems would be reviewed again to see if the error could have been highlighted sooner.

He said: "It is extremely disappointing to confirm that we have identified an administrative error with a waiting list.

"Fortunately, this has not affected the time that people have waited for their treatment.

"While I feel it is important the trust is open and that we publicly announced this error, I do not wish to alarm any patients on an outpatient waiting list, and I would encourage them not to be concerned about their treatment.

"Although it is very early in the investigation, at this stage the error appears to be a result of a member of staff not following trust policy."

He said that new methods of working, which were implemented as part of an action plan following the orthopaedic waiting affair – when about 640 people had their records altered, with some patients waiting up to 13 months for knee operations – identified the error and appropriate action was taken.

He added: "We are currently in the process of reminding members of staff of the vital need to follow trust waiting list policies, and we will provide updates on the investigation as we are able to."

n Patients who would like more information can call the Patient Advice and Liaison Service on 01733 875847.