Edith Cowan Professor sounds health warning on overdiagnosis

Moira Sim will speak at a public lecture next week.
Moira Sim will speak at a public lecture next week.

AN expert in primary healthcare is calling for debate about the merits of medical screening.

In a public lecture “Overdiagnosis: Making well people sick?” next week, head of ECU’s School of Medical Science Moira Sim will explore why diagnosing disease is not always in the best interests of the patient.

“It is generally believed that early diagnosis and treatment makes good sense as taking timely action means better results and this is usually the case,” Professor Sim said.

“However, as technology advances we are developing more and more tests that can detect problems earlier and earlier. The concern about overdiagnosis is where we are detecting diseases, such as early cancers, that were never going to grow enough to cause a problem in the patient’s lifetime.

“In these cases, it is possible that living with the diagnosis, getting side effects of treatment or having treatment that doesn’t work might be a worse outcome than if the disease went undetected.”

Professor Sim said that while screening people who have no symptoms can save lives, it should only be done after careful consideration.

“The first tenet of medicine is ‘do no harm’,” she said. “Therefore, before we start to meddle with an otherwise well population we firstly need to know the test is effective and the treatment options are going to be effective.

“Then we must consider how many lives are likely to be saved by the screening and how much improvement we can make to the quality of life.

“This must be balanced against the number of people who may be harmed by the testing or treatment.

“Finally we need to determine if we can afford it as a society, because everything we do in a world of limited resources means deciding what else we can’t afford to do.”

Professor Sim cited the example of thyroid cancer as a disease where more diagnosis was not necessarily leading to better patient outcomes.

“There is a screening program for thyroid cancer in South Korea,” she said. “In 2011 they diagnosed around 40,000 cases, more than 100 times greater than the number of people who died from thyroid cancer that year.

“It is estimated that one-third of adults worldwide have small papillary thyroid cancer, the majority of which will not produce symptoms in the person’s lifetime. Despite this, in South Korea, the majority of those diagnosed undergo treatment which can have significant side effects.”

Professor Sim said having a shared decision-making process between a patient and their doctor was a good way to promote better health outcomes.

“Finding a GP that you trust and building a relationship with them where you feel you can ask questions is one of the best things you can do for your health.

“We should welcome the increasing health literacy and interest in the community in sharing health decisions.”

The free lecture is on Tuesday, September 15. Register online at ECU’s lecture series page.