Risk of an internal injury and light exposure to radiation are the two side effects most likely to keep individuals from undergoing a colorectal cancer screening test, according to a recent study published by Current Problems in Diagnostic Radiology.

Courtney C. Moreno, MD, department of radiology and imaging sciences at Emory University in Atlanta, and colleagues wrote that colorectal cancer is the second most common cause of cancer-related deaths in the U.S., yet many adults aren’t up to date with the latest information regarding screening options such as CT colonography (CTC) and colonoscopies.

Moreno et al. surveyed more than 200 patients to learn more about factors that may be keep individuals from getting tested.

“Risk of internal injury” was the least desirable test feature, with 78 percent of respondents saying they would be “very unlikely” or “unlikely” to undergo a screening test that included such a risk. Also, more than 48 percent of respondents said they would be very unlikely or unlikely to undergo a test that listed “light exposure to radiation” as a risk.

“These results suggest that emphasizing the lower complication rate of CTC as compared with optical colonoscopy and improved patient education regarding the minimal risks of low-level ionizing radiation may improve patient acceptance of CTC,” the authors wrote.

The survey also revealed that “light sedation” was the test feature that worried respondents the least. More than 54 percent of individuals said they would be “very likely” or “likely” to undergo a test where light sedation was a risk.

“This result was also somewhat surprising, as a sedation requirement is sometimes perceived as an undesirable test feature because of the risk associated with sedation, albeit low,” the authors wrote. “Fear of sedation has been cited as a barrier to colorectal cancer screening in prior investigations. Moderate sedation utilized for optical colonoscopy can result in oxygen desaturation, hypotension, and bradycardia, although only 0.03 percent of patients develop hemodynamic compromise significant enough to require a reversal agent. A prior investigation of individuals undergoing CTC found that 63 percent of individuals selected CTC as a screening test to avoid sedation.”

The research team also found that patients have limits to the amount they are willing to paying out of pocket for cancer screenings. More than 86 percent of respondents said their limit was less than $200 out of pocket, and the amount individuals were willing to pay did not seem to be based on age, gender, race, or specific test features.

“The results of this survey suggest that an out-of-pocket cost of <$200 may increase patient acceptance of CTC,” the authors wrote.

Moreno and colleagues added that their study did have one significant limitation: patient preferences regarding a screening test’s accuracy were not taken into account. Future studies, they said, will include such information.