Supplementary Material for: Factors Affecting Recall of Different Types of Personal Genetic Information about Alzheimer's Disease Risk: The REVEAL Study

Methods: Data were obtained through a multisite clinical trial in which different types of genetic risk-related information were disclosed to individuals (n = 246) seeking a risk assessment for Alzheimer's disease. Results: Six weeks after disclosure, 83% of participants correctly recalled the number of risk-increasing APOE alleles they possessed, and 74% correctly recalled their APOE genotype. While 84% of participants recalled their lifetime risk estimate to within 5 percentage points, only 51% correctly recalled their lifetime risk estimate exactly. Correct recall of the number of APOE risk-increasing alleles was independently associated with higher education (p < 0.001), greater numeracy (p < 0.05) and stronger family history of Alzheimer's disease (p < 0.05). Before adjustments for confounding, correct recall of APOE genotype was also associated with higher education, greater numeracy and stronger family history of Alzheimer's disease, as well as with higher comfort with numbers and European American ethnicity (all p < 0.05). Correct recall of the lifetime risk estimate was independently associated only with younger age (p < 0.05). Conclusions: Recall of genotype-specific information is high, but recall of exact risk estimates is lower. Incorrect recall of numeric risk may lead to distortions in understanding risk. Further research is needed to determine how best to communicate different types of genetic risk information to patients, particularly to those with lower educational levels and lower numeracy. Health-care professionals should be aware that each type of genetic risk information may be differentially interpreted and retained by patients and that some patient subgroups may have more problems with recall than others.