It is so nice to be right.

To summarize what I wrote 2 and 3 years ago, here and here—based on my experience, patients and families will accept the theoretical risk of a future cancer if it means they’ll get an accurate diagnosis.

A new study validates that opinion.

MedPage Today reports that parents of 742 children who arrived at the emergency department with head injuries were surveyed by researchers from Toronto’s Hospital for Sick Children. The parents were queried before receiving any recommendation for CT scanning.

Parents, almost half of whom had previously known that CT scanning might cause a cancer to develop in the future, were told of the radiation risks of CT scanning in detail. The authors found that, although the parents’ willingness to go ahead with the CT scan fell from 90% before the explanation of risk to 70% after they were briefed about radiation, at crunch time only 42 (6%) of them refused to let their child be scanned.

And of the 42 who initially refused, 8 eventually went ahead with the scan after a physician recommended it.

So to put it another way: Even after they were fully informed of the potential risk of CT scan radiation to their child (lifetime risk of cancer is about 1 in 10,000, according to the authors), nearly all parents opted for the scan.

Also of note are the following: The median age of the children was 4; 12% of the children in the study had undergone at least one previous CT scan; 97% of the children were diagnosed with only concussions or mild head injuries.

An article in Scientific American puts some of the radiation risk into perspective. It is long, but worth reading — as it explains how risk has been calculated, the best guess as to the true level of risk, and what radiologists are doing to lower the radiation exposure associated with CT scanning.

According to that article, “Any one person in the U.S. has a 20% chance of dying from cancer [of any type]. Therefore, a single CT scan increases the average patient’s risk of developing a fatal tumor from 20 to 20.05%.”

I agree that CT scans should be ordered judiciously. The area scanned and the amount of radiation should be limited as much as possible.

But if you need a CT scan to help diagnose your problem, go ahead and have it. As pediatric intensivist Dr. Christopher Johnson said on the KevinMD website, “Respect diagnostic radiation but don’t have an irrational fear of it.”

Bottom line: When it comes to accuracy in diagnosis vs radiation-induced cancer risk, parents overwhelmingly chose the former.

Skeptical Scalpel is a recently retired surgeon and was a surgical department chairman and residency program director for many years. He is board-certified in general surgery and a surgical sub-specialty and has re-certified in both several times. For the last two years, he has been blogging at and tweeting as @SkepticScalpel. His blog averages over 900 page views per day, and he has over 6,300 followers on Twitter.