A spokeswoman for the Kent and Canterbury Hospital NHS Trust said that some of the 300 women whose smears had been reviewed and found to show "high-grade" abnormal cells had moved from the area or changed their GPs, and left no-forwarding address.
"The vast majority have been contacted or come forward themselves and have been undergoing treatment at the hospital, but there are some we have been unable to trace so far," she said.
The hospital is facing legal action by women whose cervical smears were found to have been incorrectly read following the biggest ever revision of smears since the NHS testing programme began in 1987.
A total of 81,000 smears taken over a five-year period were reviewed; 1,800 patients had been wrongly told they were in the clear, and of these a sixth needed urgent treatment. Two of the women underwent a hysterectomy.
The hospital spokeswoman said that "up to six patients" were considering launching legal action over the mistake which came to light in October 1995 during a routine audit when an unacceptably high number of wrongly classified smears were identified.
A review of all smear tests conducted at the hospital since 1990 was ordered in February this year, and the smears sent out for independent review.
Dr Kate Neales, a consultant gynaecologist at the trust, said yesterday that the results of the re-testing programme revealed that fewer women than expected had needed treatment.
"When the mistake was first discovered we expected a certain percentage of the number of tests we were looking at to perhaps not be clear," Dr Neales said. "We thought it could be as many as 500, but in fact, now that the programme of re-testing has been completed, we found it was less than that and was probably not as many as 300. We cannot yet be sure how many were affected because some women may have chosen to be treated by another hospital."
The retesting was completed in June and is now being evaluated. The hospital said that no individual was to blame and that the reading of smear tests was an "inexact" science with an accepted margin of error of about 5 per cent. Training and supervision procedures had been tightened up at the hospital following the mistake, she added.Reuse content