Intended for healthcare professionals

Observations Reality Check

Preventing overdiagnosis: the myth, the music, and the medical meeting

BMJ 2015; 350 doi: (Published 18 March 2015) Cite this as: BMJ 2015;350:h1370
  1. Ray Moynihan, senior research fellow, Bond University, Byron Bay, Australia
  1. raymoynihan{at}

Registrations and abstracts are now open for the third Preventing Overdiagnosis conference

Uncertainty, conflict, and controversy: the life blood of science now flows freely through the growing global debate about the problem of overdiagnosis and how to prevent it. This month a Harvard radiologist was reported attacking overdiagnosis as a “myth,” The BMJ launched a digital theme issue on the topic, and a Canadian professor put the finishing touches to a short music video on overdiagnosis, which is likely to go viral. After successful sell-out gatherings in Dartmouth College, New Hampshire, in 2013 and Oxford in 2014, seats are starting fill for the next international Preventing Overdiagnosis scientific meeting ( Supported by The BMJ, the conference takes place this year in September inside the heart of the US medical establishment, at the publicly funded National Institutes of Health, just outside Washington, DC.

The Harvard professor Daniel Kopans was quoted in the online Cancer Network publication arguing, “Overdiagnosis is a myth that has been created by a handful of individuals who provide no care for women with breast cancer.”1 A strong voice in the US debate about the merits of mammography screening, Kopans also holds several relevant patents and discloses funding from public and industry sources. The day after that attack was reported, The BMJ’s theme issue ( published a history of the overdiagnosis science in breast cancer, which acknowledged uncertainty and controversy but concluded that, rather than a myth, “the existence of overdiagnosis is now generally accepted.”2

But perhaps the most important sign that the debate about overdiagnosis has come of age is the music video released this month by the Canadian pharmacy professor James McCormack, who is based at the University of British Columbia. His previous YouTube videos, which use popular songs to introduce sometimes dowdy concepts such as evidence, polypharmacy, and the Choosing Wisely campaign, have gone viral, with some approaching 100 000 views. McCormack’s latest, Bridge Over Diagnosis, may well prove as popular, offering an entertaining way to educate and inform about this complex and often counterintuitive problem, all set to the soundtrack of Simon and Garfunkel’s classic hit record (

More conventional pedagogical material can be found in The BMJ’s Too Much Medicine series on expanding disease definitions and the risk of overdiagnosis, which has been running over the past couple of years and now features articles on almost 10 conditions ( Wiener and colleagues showed how changes in diagnostic technology drove a dramatic increase in the detection of small blood clots, resulting in overdiagnosis and overtreatment of pulmonary embolism.3 Cundy and colleagues argued that a 2010 expansion of the definition of gestational diabetes could triple the number of diagnoses among pregnant women, producing much overdiagnosis.4 And Martin and colleagues concluded that many people were being given a diagnosis of mild hypertension and treated for it, despite the lack of evidence of benefit.5

The most recent Too Much Medicine article estimated the extent of overdiagnosis of abdominal aortic aneurysm (AAA).6 Researchers in Sweden and Denmark offered preliminary estimates that up to half of the aneurysms detected in screening programmes would not go on to cause any harm and were thus “overdiagnosed.”

Let’s build the evidence base

The Too Much Medicine series is starting to reveal a pattern across a range of different conditions: the diagnosis and treatment of conditions in an increasing number of people with milder problems or at lower risks, some of whom will be helped, but a proportion of whom will be harmed. Disease definitions are being broadened, thresholds lowered, and diagnostic processes changed in ways that increase patient populations without rigorous investigation of the potential harms of those changes or proposed systems to mitigate those harms.

As the series shows, the evidence for overdiagnosis of some conditions is still speculative, with no numerical estimates of its magnitude. In other conditions the evidence is more mature, and, while uncertainty persists, numbers are starting to emerge from the ongoing scientific investigation of the problem. In addition to building an evidence base to inform responses in practice and policy, the series is creating a treasure trove of methodologies for other researchers interested in investigating the harms done by medicine’s expanding diagnostic empire, as well as its benefits. And, perhaps most importantly, each of the articles is explicit about the limitations of the evidence, underscoring a wider aim of those investigating the problem of too much medicine: to try to avoid doing any more harm when attempting to wind it back.

The Preventing Overdiagnosis conference in September this year is devoted to sharing and debating this emerging science of overdiagnosis, starting with its definition, which is still evolving.7 Unlike many medical meetings, this one is multidisciplinary and totally free of industry funding. Plenary speakers will include the breast cancer specialist Laura Esserman, of the University of California San Francisco, Hyeong Sik Ahn from Korea University on the epidemic of thyroid cancer overdiagnosis, and Cynthia Pearson, executive director of the US National Women’s Health Network, who will provide an informed citizen perspective. Let us hope that, along with the science, the uncertainty, and the controversy there will be much merriment and music—and, who knows, maybe even some myth busting.


Cite this as: BMJ 2015;350:h1370


  • Competing interests: RM is a member of the scientific steering committee planning the Preventing Overdiagnosis meetings, an adviser to The BMJ on its series, and a fan of James McCormack’s evidence informed music videos.

  • Provenance and peer review: Commissioned; not externally peer reviewed.


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