Media focus on failures of screening programmeBMJ 1997; 314 doi: https://doi.org/10.1136/bmj.314.7094.1630 (Published 31 May 1997) Cite this as: BMJ 1997;314:1630
Channel 4's recent Dispatches programme on cervical screening focused on one poorly performing laboratory. Dr Jane Johnson says it is important that the whole screening programme is not tarred with the same brush.
The NHS cervical screening programme is the envy of the world. Since the introduction of the central call and recall system and incentive payments for general practitioners in 1989-90, the percentage of women aged 20-64 being screened in England and Wales has increased from 50-60% to over 80%, and the death rate from the disease is falling steadily at about 7% a year. It has been estimated that the screening programme may save up to 7000 women's lives every year.
The number of new cases of invasive cancer being diagnosed has fallen by 50% in 10 years, and most new cases are detected at a very early stage, before symptoms develop, when there is an 85-95% cure rate. More importantly, almost all disease is detected at an even earlier pre-invasive stage, when the cure rate approaches 100% and treatment is on an outpatient basis with preservation of fertility. This is a success story and one that should be broadcast to women everywhere to encourage them to continue to have regular smear tests.
Of course, as in every system that was set up in a haphazard fashion with no identified funding and to differing standards throughout the country, some screening laboratories will perform poorly. It is with this in mind that the national coordinator of the programme, Julietta Patnick, has set up regional quality assurance teams tasked with examining reporting rates of laboratories against the standards published by the screening programme, the Royal College of Pathologists, and the British Society for Clinical Cytology. Laboratories found to be performing outside the target ranges have been identified and the reasons for this examined and, where necessary, corrected.
In doing this, of course, such laboratories are coming to people's attention. Previously, they were left to monitor their performance themselves, or not. Unfortunately, such a poorly performing laboratory, which no longer conducts tests, was the subject of Channel 4's Dispatches programme on 22 May. Press releases resulted in articles in the Times and Guardian that concentrated on the failures of the system with only a passing reference to the screening programme's success. In fact, this has been the flavour of all recent media attention, with the implication that the whole screening programme is unreliable.
An expert, who retired long before proficiency tests were introduced, was shown interpreting slides and suggesting that obvious mistakes had been made. It is easy to evaluate changes when you know that a women has developed cancer: those cells must be significant. It is just as important not to overdiagnose abnormalities so that women are not subjected to unnecessary extra examinations, let alone unnecessary treatment. Screening is not diagnosis. It is like walking a tightrope between false negatives and false positives. This is where automated screening techniques come in, with claims of being able to detect more abnormalities than manual methods. Most smear tests are negative. It would be beneficial to detect more abnormalities only if they prove to be genuinely precancerous, and this has not yet been properly evaluated.
Those of us who are working hard to run a successful screening programme are concerned that our staff are insulted and demoralised by the continued accusations of incompetence. We fear that the women whom we serve will be led to think that the whole programme is useless and so not bother to be screened, or be attracted to have unevaluated tests outside the national programme.
Dr Johnson is chairman of the British Society for Clinical Cytology and sits on the advisory committee to the Department of Health on cervical screening