"Unnecessary Imaging Tests” in ER Aren’t Necessarily Unnecessary

There is no such thing as absolute certainty.

John Stuart Mill (1806-1873), On Liberty

We live in an age of great expectations of the certainty of imaging tests. This week a patient said to me, “My husband went to the emergency room with belly pain, and the doctor didn’t know what was wrong. Why didn’t the doctor just do a CT-scan to make certain nothing was wrong”?

The certainty of radiology imaging tests is an illusion. There is no such thing as absolute certainty even with advanced technologies. In a survey of 435 ER physicians 97% said imaging studies they ordered were “unnecessary “ (John Commins, “97% of ED Physicians Order Unnecessary Imaging Tests,” HealthLeaders Media, March 30, 2015).

There are various explanations for these “unnecessary” imaging tests- medical legal fears, insensitivity to costs because insurers will pay, blind beliefs in technology, doing something to save time and satisfy patients, a compulsion to leave no stone unturned, public expectations that imaging tests represent the final answer.

But it’s more fundamental than that. According to Hemal Kanzaria, MD, an emergency room physician in Los Angeles, “Overtesting is not due to physicians’ lack of knowledge or poor medical knowledge, but reflects a cultural response both within and outside of medicine to uncertainty and error… We need to address this cultural intolerance of uncertainty... this cult of blame that triggers the malpractice system. Outcomes do not take into account factors that led to a test…the widespread beliefs that are held in society, including the perception that error is the cause of any bad outcome, or that technology can cure all of our problems. Or that catching things early is always beneficial.”

As the George and Ira Gershwin’s song in Porgy and Bess “ said of the applicability, impact, and truth of Biblical stories on one’s life, “It Ain’t Necessary So, ” imaging tests in the ER aren’t necessarily unnecessary, nor are negative outcomes necessarily due to physician error or poor judgment, but to widespread cultural beliefs that if something goes wrong, someone did something wrong , that someone is to blame, that technology eliminates uncertainty, and that poor outcomes should be grist for the malpractice mill.

The uncertainty of why imaging tests were ordered, and the uncertainty expectations of what they reveal, show the limits of outcomes research, and the limits of judging physician performance by this research.