Only about a third of patients surveyed at one U.S. medical center said their doctors told them about the possible risks of a CT scan, such as radiation exposure, a new study finds.
Researchers, who published their findings in JAMA Internal Medicine on Monday, also found that most patients thought their doctors made the final decision to have the scans.
"I think that sounds pretty consistent of what my experience would be as a patient, physician and with family members," said Dr. Howard Forman, professor of diagnostic radiology and public health at the Yale School of Public Health in New Haven, Connecticut, who was not involved with the new study.
The new study jibes with previous research that found people are unaware of the radiation risks posed by CT scans.
CT scans are high-powered X-rays that provide clearer images but expose patients to between ten and 100 times as much radiation as a normal head or chest X-ray.
For the new study, Dr. Tanner Caverly, from the University of Colorado Anschutz Medical Campus in Aurora, and colleagues surveyed 286 patients getting a CT scan at the Denver Veterans Affairs Medical Center from November through December 2011.
Of the 271 patients that returned their surveys, 35 percent said they discussed the risks of a CT scan with their doctors and 62 percent believed the final decision to have the scan was made by the doctors.
Only 17 percent of the patients said they were involved in the decision-making process and discussed risks and benefits with their doctors.
But even when doctors were discussing the potential risks, their patients ended up being no more informed than people who didn't talk with their healthcare providers.
"It's likely that many physicians also do not know the risks, and so it's not surprising that even when there are discussions with patients about risks and benefits of the procedure, patients clearly still do not understand the true risk of radiation exposure," wrote Dr. Patrick O'Malley, a deputy editor of the journal, in an note accompanying the new study.
One study from the National Cancer Institute estimated there would be about 29,000 future cancers related to scans done in 2007 alone. That year, Americans had about 72 million total CT scans, which can cost from a few hundred dollars to several thousand dollars.
Forman told Reuters Health there are a few ways to address the problem of patients not being told about the risks of CT scans, including educating doctors and empowering patients to ask questions.
"I think we need to empower healthcare consumers/patients much more to have complete understanding and control of their care and its delivery. I think physicians are sometimes offended by patients who ask too many question and I think that's something we need to change," Forman said.