Patient understanding of benefits, risks, and alternatives to screening colonoscopy

While several tests and strategies are recommended for colorectal cancer (CRC) screening, studies suggest that primary care providers often recommend colonoscopy without providing information about its risks or alternatives. These observations raise concerns about the quality of informed consent for screening colonoscopy.

We conducted a telephone survey (August 2008 to September 2009) of a convenience sample of 98 patients scheduled for a screening colonoscopy to assess their understanding of the procedure's benefits, risks, and alternatives and their sources of information.

Fully 90.8% of subjects described the purpose of screening colonoscopy in at least general terms. Just 48.0% described at least one risk of the procedure. Only 24.5% named at least one approved alternative test. Just 3.1% described the minimal required elements for informed consent: the benefit of colonoscopy, both of the major risks, and at least one approved alternative test. Compared to subjects with higher levels of education or income, fewer subjects with lower levels of education or income could name at least one risk of colonoscopy or one approved alternative test to colonoscopy. For benefits, risks, and alternatives, a smaller percentage of subjects responding reported obtaining information from their doctors than from other sources.

Patients scheduled for screening colonoscopy have limited knowledge of its risks and alternatives; subjects with lower education levels and lower income have even less understanding. For patients who do not receive additional information until they have begun the preparation for the test, the quality of informed consent may be low.