A private laboratory publicly criticised by the North Western Health Board over how it handled cervical smear tests has been cleared of producing inaccurate test results.
A report commissioned by the board showed that the work by Claymon Laboratories was "well within acceptable standards".
Dublin-based Claymon Laboratories undertook to process over 2,115 smear test slides for the health board between August and December, 1997, after a 16-week backlog developed at Sligo General Hospital's laboratories. However, an audit in January 1998 found fewer abnormal smears than expected had been identified among the batch, and they were sent to a Glasgow laboratory for rechecking. It said up to 69 slides had incorrectly been found to be negative.
The health board commissioned British-based Healthcare Risk Resources International (HRRI) to investigate. In its final report, a copy of which has been seen by The Irish Times, HRRI found that the clinical reviews of the slides by the screeners subcontracted by Claymon Laboratories "were performed to well within acceptable standards".
In the case of one of the screeners there was significant misclassification in just two out of 500 slides. In the case of another this misclassification occurred in four out of 1,615 slides. In each case the rate was below 1 per cent.
HRRI contracted Dr Winifred Gray, consultant pathologist at the John Radcliffe Hospital, Oxford, independently to examine the allegedly false slides, borderline upgrades and slides deemed to have insufficient cells to make a judgment.
"However, in the opinion of HRRI there has been misclassification to a significant extent such that may affect clinical outcome in six of the cases reviewed," the report concluded.
However, it notes that the slides from women with a possibly higher clinical risk had been selected out of the sample sent to Claymon. This explained why the results produced by Claymon found fewer abnormal smears and vindicated its results, Claymon managing director Mr Eamonn Madden said. Although he had some criticisms of the report, Mr Madden welcomed its conclusion that the clinical work of his firm was well within international acceptance levels.
In a statement issued late last night the board said the report stated that Sligo General Hospital "took appropriate action to alert the North Western Health Board. This response minimised, as far as possible, the risk to patients of misdiagnosis of the slide results and the potential loss of health or life."
The board said that "this risk to patients has always been the board's paramount consideration" and that its chief executive was satisfied the hospital had acted appropriately.