Early adoption of BRCA1/2 testing:: Who and why

Purpose: Relatively little is known about the characteristics of women who chose to undergo BRCA1/2 testing soon after testing became available, including how they became aware of and chose to pursue testing. Diffusion of innovation theory states that acceptance of an innovation is a function of the potential adopter's value for innovation and perceptions of the compatibility, complexity, and relative advantage of the innovation. These factors may contribute to early uptake of BRCA1/2 testing. The purpose of this study was to describe the characteristics of women who were early adopters of clinical BRCA1/2 testing and to determine whether diffusion theory explains variation in uptake of testing after participation in genetic counseling for BRCA1/2 testing. Methods: A retrospective cohort study of participants in genetic counseling for BRCA1/2 testing was conducted at a clinical program in a large academic health system. Measures included components of diffusion of innovation theory (participant's value for innovation, i.e., innovativeness, and perceptions of the compatibility, complexity, and relative advantage of BRCA1/2 testing), characteristics of how the participant became aware of and sought BRCA1/2 testing, and decisions about testing after counseling. Results: From the 229 respondents, 71 (31%) had undergone testing at the time of the survey. Fifty-seven women (25%) had sought BRCA1/2 testing because a family member had breast or ovarian cancer and 37 (16%) because they had breast or ovarian cancer. Only 15 women (7%) reported seeking testing because of a physician's recommendation. After multivariate adjustment, higher innovativeness and higher ratings of the compatibility of BRCA1/2 testing were associated with undergoing testing after counseling [relative risk (RR) 1.76, 95% confidence interval (CI) 1.2-2.6]. However, ratings of the complexity or relative advantage of testing were not associated with testing decisions. Higher innovativeness was associated with being the first in the family to undergo testing (RR 4.85, 95% Cl 1.6-14.9), becoming aware of BRCA1/2 testing through the media (RR 1.50, 95% CI 1.0-2.4), and being aware of BRCA1/2 testing prior to counseling (RR 1.25, 95% CI 1.1-1.4). Conclusions: The uptake of BRCA1/2 testing among women undergoing genetic counseling was associated with innovative characteristics of the participant and the perceived compatibility of the test with existing values and needs, but not with the complexity or relative advantage of the test. Most early adopters had heard of BRCA1/2 testing from a source other than their physician and had sought testing because of a personal or family member's cancer diagnosis. These findings can inform predictions surrounding the introduction of future genetic susceptibility tests and strategies for guiding the further diffusion of BRCA1/2 testing.