Some doctors need to be more discerning about the criteria they use when referring people for X-rays, not least because X-rays can initiate cancers. A lumber spine X-ray, for example, has been estimated to carry a one in 15,000 risk of initiating a fatal cancer by Britain's national radiological protection board*.
A new European Union directive on radiation protection, scheduled to become law throughout the EU on May 13th, 2000, aims to reduce the radiation dose to the general public.
According to Mr Liam Murray, president of the Irish Institute of Radiography, the reduced exposure will be achieved using the ALARA (as low as reasonably achievable) principle and the "justification" principle, that is, where the specific X-ray produces sufficient benefit "to offset the radiation detriment that it causes".
While the benefits of X-rays usually outweigh the risks, "there is no known safe level of radiation. So, in itself, no exposure can be beneficial. The benefit to the patient is in the diagnostic information that the X-ray produces", he says.
Many X-rays provide no useful diagnostic information, while some studies suggest a reduction of some 50 per cent of X-rays would have no detrimental impact on the care and treatment of patients.
With the new EU legislation, GPs will have to justify why they are requesting a patient to be X-rayed.
Mr Murray said: "There's a perception both with doctors and the general public that if you come for an X-ray and you have your back X-rayed or your stomach X-rayed that it'll tell you everything. If you have a pain, that it will identify it. But in fact a lot of these pains are muscle strain, nerve problems even a disc problem in your back and it will not show on a plain film radiograph.
"So a lot of examinations are being carried out which are yielding no diagnostic information or no useful diagnostic information. It's well intentioned, but there's no yield from it - it doesn't alter the patient's care, treatment or the course of treatment."
What he does not say is that it also needlessly exposes people to the possibility of actually initiating a cancer - a worthwhile risk if the X-ray is required, but surely irresponsible if it is not.
Some 3,000 GPs around the State are receiving copies this month of the booklet Making the Best Use of a Department of Clinical Radiology - Guidelines for Doctors, published by the Royal College of Radiologists in Britain.
According to Mr Murray, it is the first time that an initiative has been taken to disseminate X-ray referral criteria to general practitioners. Now that GPs are specifically included in the EU directive, "they must take responsibility for the justification of the examination requested", he said.
St John's Hospital in Limerick has audited the implementation of the guidelines since April 1st, 1995. "We've actually managed to get a 30 per cent reduction in hospital-generated referrals by applying the guidelines," said Mr Murray.
They have an induction day every six months when there is a change of doctors. Each is given a copy of the booklet. "We lay out the parameters under which we would do an X-ray and if they don't meet these guidelines, we might not necessarily refuse but we'll certainly argue. And we'll ask them to come down and justify why they want it."
"Now, if we could also get the GPs to be more discerning in their referrals it will again shorten the waiting time, if you like, to get into us and to get the report back out to the GP. So everyone should benefit. It should be a virtuous circle, hopefully. We're not necessarily doing less work but we like to think that the work we're doing is more meaningful."
Workplace referrals often involve backache, with the lumber spine - the lower back - one of the most popular examinations. Yet the recommendation in the guidelines is that X-rays are "not indicated routinely".
As Mr Murray said: "If you had a car that is 45 years old, it would have a bit of rust and be showing a bit of wear and tear. Now that's what your back is. If we X-ray you, we'll see that. But we'd expect to see that in a person of 45 or 50. But it's not going to change the management. It's not going to change the treatment. The doctor's not going to do anything different for you. So are you any the wiser having had the X-ray? Probably not."
* For cancer risks from X-rays, see Frequently Asked Questions at: http://www.nrpb.org.uk
jmarms@irish-times.ie
