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Better safe than sorry not always true when it comes to diagnoses


Is the healthcare system overdosing, overtreating and overdiagnosing the healthy? According to a commentary article by researchers at Bond University in Australia and the Institute for Clinical Evaluative Sciences (ICES) in Toronto, overdiagnoses of various diseases may be putting healthy patients at risk.  

Narrowly defined, overdiagnosis occurs when people without symptoms are diagnosed with a disease that ultimately will not cause them to experience symptoms or early death. It is a phenomenon that has become more common with sensitive screening techniques for cancer and imaging techniques that are capable of finding ever smaller tissue abnormalities.  

“The good intention of early detection makes way for negative effects like unnecessary labelling, the harms of unneeded tests and therapies, and the cost of wasted resources that could be better used to treat or prevent genuine illness,” says one of the study’s authors, Dr. David Henry, CEO of ICES.  

Drivers of overdiagnosis:

  • Technological changes detecting ever smaller 'abnormalities'
  • Commercial and professional vested interests
  • Conflicted panels producing expanded disease definitions and writing guidelines
  • Legal incentives that punish underdiagnoses but not overdiagnoses
  • Health system incentives favouring more tests and treatments
  • Cultural beliefs that more is better; faith in early detection unmodified by its risks  

“Concern about overdiagnosis does not preclude awareness that many people miss out on much needed healthcare. On the contrary, resources wasted on unnecessary care can be much better spent treating and preventing genuine illness. The challenge is to work out which is which, and to produce and disseminate evidence to help us all make more informed decisions about when a diagnosis might do us more good than harm,” says Henry.   An international conference "Preventing Overdiagnosis" will be held September 10-12, 2013 in the United States, hosted by The Dartmouth Institute for Health Policy and Clinical Practice, in partnership with the BMJ, the leading consumer organization Consumer Reports and Bond University, Australia.

Authors: Ray Moynihan, Jenny Doust, David Henry

The commentary “Preventing overdiagnosis: how to stop harming the healthy?” is in the current issue of BMJ.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.



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