Supplementary Material for: Interest in Genetic Testing for Hereditary Cancer Risk: Associations with Genetic Familiarity, Self-Efficacy, and Sociodemographics

Introduction: Genetic testing (GT) for hereditary cancer risk enables early detection and prevention, yet many individuals who could benefit do not pursue testing. Limited genetic familiarity and lower genetic self-efficacy may act as barriers. This study examined relationships among patient-reported genetic familiarity, genetic self-efficacy, sociodemographic characteristics, and interest in GT.

Methods: Data were drawn from the Early Detection of Genetic Risk (EDGE) baseline survey (n = 2,319), distributed to a random sample of patients aged ≥25 years from participating primary care clinics in Washington, Montana, and Wyoming. Patients were contacted via email and mailed letter in January 2021, prior to implementation of the EDGE intervention. Bivariate logistic regression assessed associations between sociodemographic factors and genetic familiarity and self-efficacy. Multivariable logistic regression examined independent associations between sociodemographic factors, genetic familiarity, genetic self-efficacy, and interest in GT.

Results: In multivariable analyses, higher genetic familiarity was strongly associated with interest in GT (adjusted odds ratio [aOR] = 2.67; 95% CI: 1.47–4.86). Higher income (aOR = 2.43; 95% CI: 1.43–4.13) and female sex compared with male (aOR = 1.80; 95% CI: 1.16–2.40) were also positively associated with interest in GT. Participants aged over 65 years were significantly less likely to express interest in GT (aOR = 0.28; 95% CI: 0.13–0.60).

Conclusion: The strong association between genetic familiarity and interest in GT suggests that increasing basic genetic knowledge may be an effective starting point for educational interventions aimed at improving testing uptake. Understanding drivers of interest in GT can inform targeted strategies to enhance hereditary cancer prevention and early detection efforts.