Measuring the Impact of Quantitative Information on Patient Understanding: Approaches for Assessing the Adequacy of Patient Knowledge about Colorectal Cancer Screening.

Patients who viewed quantitative information in a decision aid about colorectal cancer screening were more knowledgeable about nonquantitative information and were more likely to have adequate knowledge according to a variety of approaches for assessing that, compared with individuals who viewed only qualitative information. This result supports the inclusion of quantitative information in decision aids.Researchers assessing patient understanding should consider a variety of ways to define adequate knowledge when assessing decision quality.