What physicians think about the need for informed consent for communicating the risk of cancer from low-dose radiation.

BACKGROUND: The National Institute of Environmental Health Sciences, a subsidiary of the Food and Drug Administration, has declared that X-ray radiation at low doses is a human carcinogen.

OBJECTIVE: The purpose of our study was to determine if informed consent should be obtained for communicating the risk of radiation-induced cancer from radiation-based imaging.

MATERIALS AND METHODS: Institutional review board approval was obtained for the prospective survey of 456 physicians affiliated with three tertiary hospitals by means of a written questionnaire. Physicians were asked to state their subspecialty, number of years in practice, frequency of referral for CT scanning, level of awareness about the risk of radiation-induced cancer associated with CT, knowledge of whether such information is provided to patients undergoing CT, and opinions about the need for obtaining informed consent as well as who should provide information about the radiation-induced cancer risk to patients. Physicians were also asked to specify their preference among different formats of informed consent for communicating the potential risk of radiation-induced cancer. Statistical analyses were performed using the chi-squared test.

RESULTS: Most physicians stated that informed consent should be obtained from patients undergoing radiation-based imaging (71.3%, 325/456) and the radiology department should provide information about the risk of radiation-induced cancer to these patients (54.6%, 249/456). The informed consent format that most physicians agreed with included modifications to the National Institute of Environmental Health Services report on cancer risk from low-dose radiation (20.2%, 92/456) or included information on the risk of cancer from background radiation compared to that from low-dose radiation (39.5%, 180/456).

CONCLUSION: Most physicians do not know if patients are informed about cancer risk from radiation-based imaging in their institutions. However, they believe that informed consent for communicating the risk of radiation-induced cancer should be obtained from patients undergoing radiation-based imaging.