Dr Phil Hammond

Do cervical smears do more harm than good? I don't mean the mild embarrassment of Sister Parker saying "Pop your little panties down and make your legs like a frog". Or the buttocks-off-the-couch discomfort of a cold speculum. I'm talking about the psychological torment caused by the abnormal smear result. The vast majority of women who test positive have nothing to worry about - they will never get cervical cancer - and yet just one mildly abnormal result can induce a lifetime of anxiety. The hallmark of a good screening test is that it should accurately identify those at an early stage of a serious disease without inducing mass hysteria in those who aren't. Cervical screening, alas, fails miserably. Why?

Mass smearing was introduced in the UK in 1966 without any proper prior evaluation. No randomised, controlled trials were done and no-one had any proof it would work - just the (horribly wrong) assumption that any abnormal cells in the smear meant you were destined to get cervical cancer so you'd better have a portion of your cervix or the whole womb removed. Women having smears couldn't give informed consent because nobody knew what the information was. There were only hunches.

By today's standards, cervical screening might never have been allowed to proceed. The recent thumbs-down to prostate screening, until there is concrete proof of its effectiveness, will mean it may not be with us for 10 years, if ever. In the meantime, many thousands of men will die of prostate cancer and for those who suffer and treat the disease, any chance of picking up an early warning sign in time for cure seems better than no chance. But screening now would mean imposing an inaccurate test on a great chunk of the male population - well over 90 per cent of those with a mildly abnormal result would have nothing to worry about. Cue mass panic and unnecessary prostate removals with nasty side effects.

Sadly, we were much more gung-ho in the Sixties and cervical smearing is now so widespread that we can't suddenly stop doing it to find out if it works. We'd need to compare the cervical cancer rates in comparable groups of screened and unscreened women over many years but that, alas, would be unacceptable to women, ethics committees, doctors and government ministers who have been brainwashed into believing cervical screening exists, therefore it must be a good thing. We will never know the answer for sure - all we can do is make retrospective assumptions.

We do know, however, that deaths from cervical cancer are rare - just over one in 10,000 women over the age of 20. In my home city of Bristol, the incidence of cervical cancer deaths hasn't changed at all, despite 30 years of screening. Nationally, mortality is declining but most steeply in older women who have never been screened anyway. We could charitably assume that cervical screening has prevented a rise in cervical cancer that might have resulted from the promiscuous Sixties (more sex means more wart viruses means more cancer), but of 32 women who died under the age of 45 in north east Scotland between 1982 and 1991, 63 per cent had been screened and still succumbed.

Screen believers cannot blame lack of uptake for the failure to eradicate the cancer (many GP practices achieve above 95 per cent smearage of "at risk" women) and the pressure is now on to screen more frequently and intervene more quickly, causing a lot more anxiety and surgery without proven benefit. In medicine, we always have to be seen to be doing something when the greatest skill is to do nothing. But try explaining that to a lawyer.

Some doctors in charge of administering cervical screening programmes remain sceptical of the benefits and yet are forced by public expectation, government policy and the fear of litigation to carry on. As Dr Raffle from Bristol Health Authority wrote in The Lancet in 1995: "The number of smear abnormalities is excessively high in comparison to the incidence of the malignancy we are trying to prevent.... Despite good organisation of the service, much of our effort in Bristol is devoted to limiting the harm done to healthy women and to protecting our staff from litigation as cases of serious disease continue to occur."

During each five-year screening round in Bristol, there is the potential to prevent 200 deaths from cervical cancer. During the same period, over 15,000 smeared women are told incorrectly that they are "at risk" from cancer, 5,500 are further investigated and often treated for a disease that would never have troubled them and many are being left with lasting fears about cancer, difficulties in obtaining life insurance, and worries about the effectiveness of treatment, their sexuality and their reproductive ability. And all because of a mistaken medical hunch. Thank God I'm a bloke

Next week: How can the anxiety of an abnormal smear be reduced?