Medical Matters'Doctors differ and patients die" is an old but blunt maxim. A more modern version could be "Doctors make mistakes while patients suffer," writes Muiris Houston
And an equally valid variation might go: "Poor systems of care produce poor outcomes for patients."
Whatever the conclusions of the report into the misdiagnosis of women with symptomatic breast disease at Portlaoise hospital, one thing is clear: the patients who put their faith in the service at the midlands hospital have had their trust in the health system well and truly shattered.
While I have every sympathy for these women, I wonder how many of them went for a mammogram believing it was the perfect test to assess whether they had breast cancer? I suspect quite a few had this view of medical technology.
Perhaps it is the medical profession who are to blame for this illusion of medical infallibility. Given the propensity in the past for doctors to encourage a God-like belief in their abilities, this may well be the case. Or maybe it is the fault of modern technology. We see problems with cars, aeroplanes and washing machines accurately diagnosed and quickly put right. Why shouldn't we expect the same accuracy and efficiency when we are unwell?
One of the reasons is the human condition. Despite the many advances made in surgery, and the ready replacement of faulty parts, we do not expect to be "back on the road" immediately after surgery in the way a car is ready to go after a major service.
And it is the same human element that means we can never guarantee perfection in medical diagnosis and treatment. Because every test result must be interpreted by a healthcare professional, mistakes will be made.
Even in the best cancer centres in the world, using the most up-to-date equipment and a multidisciplinary approach, medical error will occur. The best that medicine can offer is to work towards minimising the risk of misdiagnosis.
Modern consumers tend to assume that medical tests are 100 per cent accurate. But the reality is that they are not: every X-ray, blood test and biopsy result can be either falsely positive or falsely negative.
A person with a false positive result does not have the disease even though the test suggests they do. This can result in the need for the individual to undergo further investigations that are unnecessary or they may be given treatment that is unpleasant and even dangerous.
False negative results occur in those people who have the disease, but the test indicates they are disease free. At a minimum, it will mean a delay in the accurate diagnosis of the disease; it may even result in the need for more extreme treatment than would have been necessary if the correct diagnosis had been made in the first place.
Much has been written about the report of the National Quality Assurance Group for Symptomatic Breast Disease and the need to implement its guidelines for centres of excellence. At no point do its authors offer the panacea of perfection.
But the report is upfront about the limitations of its recommendations. For example, on the specific issue of examining, under a microscope, the cells from a fine needle breast biopsy, it specifies an "acceptable" level of misdiagnosis.
This is an honest acknowledgement that even in conditions of best practice, up to one in 20 women may be told that they do not have breast cancer following a fine needle biopsy, even though in reality they have the disease. (The greater use of biopsy rather than fine needle aspiration reduces the risk of a misleading result).
So much for the science. The reality for us as humans is that, faced with significant bad news in the form of a cancer diagnosis, we react emotionally. Few of us, no matter what our training or background, possess the sangfroid to be immediately objective.
This is where our perception of risk comes into play. A 2005 EU study looked at people's perceptions and experiences of medical error across Europe.
There was quite a variation between countries, with something of a North-South divide emerging. The Scandinavian countries and Austria have the most trust in medicine, while people in Italy, Cyprus and Poland were more concerned about medical errors and have less trust in health professionals.
Significantly, people's awareness of the issue differed from their actual experience. While almost four out of five respondents said they had heard or read about medical error, less than one in five indicated they had either personal or family experience of medical error in a hospital.
And while most of those surveyed said it is the responsibility of the healthcare system to ensure the quality of treatment, a substantial number recognised that patients have a role to play in avoiding medical error.
Some of us calculate risk, while others are sensitive to hazards. All of us perceive risk differently. Following recent events there is a need for the health system to prioritise the communication of risk in a way that is easy for all of us to understand.
Dr Muiris Houston is pleased to hear from readers at mhouston@irish-times.ie but regrets he cannot reply to individual medical queries.