This television news report on a New England Journal of Medicine article explores the potential cancer risks from high doses of radiation used in CT scans. The report is based on a significant paper, consults a variety of sources and draws on a physician medical editor to put the findings in context. It eventually delivers the appropriate caveats.
Yet its presentation by the anchor and reporter fundamentally overstates the tests’ real risks to individuals. It does not clarify, until the end of the segment, that the risks for an individual patient are quite small.
This segment demonstrates a common practice in health journalism: Using fear to get audience attention, then explaining, eventually, that there is not that much to worry about. This does not serve the public, or health journalism, particularly well.
A viewer would have been better served by a segment that says simply that CT scans may be overused–and that children and young people, especially when subjected to multiple scans, could face increased cancer risk. The solution: Doctors and patients need to be more discriminating in their use of this technology, especially in people under 25.
It is worth mentioning that broadcast health journalism is strengthened when it refers viewer to the web for more information. In this case, the ABC web site had some good additional material viewers should have been told about–and that provided a lot of the useful detail the TV broadcast did not.
The segment fails to mention how expensive the scans are. This is a significant omission.
While it’s true that the journal article’s focus is the potential danger from the scans’ radiation, the issue of overuse is introduced early on and sustained throughout the report. The financial costs of that overuse should have been mentioned.
Prices for CT scans range from $300 to $2,000 and up, depending on the nature of the scan, which facility administers it and whether it is covered by insurance.
The story focused on harms, so quantifying the benefits of CT scans is not imperative in this case.
The segment reports the most provocative figures appearing in the study: that up to 2 percent of cancer cases may be caused by CT radiation over the next 20 years, and that the dose is 100 to 200 times greater than an X-ray.
But the study’s conclusions are less dramatic: that perhaps one-third of CT scans are unnecessary (this is based on a straw poll of physicians at a meeting, not rigorous science), that the radiation dose appears to be most dangerous to children (which the study documents rigorously), and that doctors and radiologists need to be more educated about the use of these tests.
The most important facts to a viewer–the absolute risks of getting various cancers for those who have and have not had CT scans–are not reported.
While the risk projections of various types of cancer and different radiation exposures published in the study are based on rigorous data collection and modeling, the conclusions are inferences and estimates.
They are not reports of cases of disease in a population of people who have had CT scans and were followed over time.
The segment fails to make this clear.
The segment engages in disease mongering: The host starts with a provocative question about the scans’ capacity to cause cancer, raised by an authoritative journal article. The reporter explores this theme at length. But both raise fears about cancer risk that are not justified by the published article.
Indeed, the network’s physician medical editor at the end says plainly that the risk from a single scan is practically zero–he "guarantees" it. If his statement is correct, then the segment itself certainly is an example of disease-mongering.
The segment does a good job of sourcing: The journal article is highly credible, sources on both sides of the controversy are given airtime and the physician medical editor at the end puts the findings in context.
The range of sources also represents all of those responsible for CT overuse: community physicians, radiologists and patients.
The journal article’s conclusion that scans are overused implies that other diagnostic tests are available. But the broadcast segment does not specify what they are.
The segment makes clear that CT scans are ubiquitous–indeed, that’s the focus of the story.
Reporting the specific facts–that annual use of CT scans has climbed from 3 million in 1980 to over 62 million today–is very useful in this context.
Because the segment focuses on the scans’ wide use, this criterion is not applicable.
This segment does not appear to draw heavily from Columbia University’s press release.
It is worth noting that the university’s press release is more careful and nuanced in its description of the results than the television broadcast.