Comparing Direct vs Indirect Methods for Cascade Screening
Long QT Syndrome · Familial Hypercholesterolemia · Ethics
An important aspect of successful genomic medicine implementation is developing effective approaches for screening at-risk family members after probands are identified, also known as cascade screening. Most cascade screening studies conducted to date have been conducted outside the US, and very few studies have used a rigorous approach involving a comparator group or randomized controlled design. A major question in the field is how to most effectively implement cascade screening, given commonly cited communication barriers, while respecting privacy among probands and family members. This study will conduct a randomized controlled trial to assess direct contact of relatives by study team members vs indirect, or proband-initiated, contact. We will assess efficacy of the cascade screening intervention, patient-centered outcomes regarding mental, physical, and psychosocial outcomes in probands and family members, and implementation evaluation outcomes.
Individuals who are known to carry the KCNQ1 Met224Thr or APOB Arg3527Gln variant will be eligible to participate. After providing consent and being deemed eligible, individuals will be randomized in a 1:1 manner into the direct or indirect contact of family members arm of the study. The randomization will be stratified by variant to ensure equal representation of each variant in the study arms. Individuals in the indirect arm will be instructed to contact their first-degree family members about the opportunity to be screened. They will be provided with a disease-specific pamphlet and a family letter explaining the cascade screening. In the direct arm, probands will be advised that the study staff will be contacting their family members. They will be instructed to also contact their family members prior to the study team contacting them. Approximately two weeks after this meeting with the proband, the study staff will mail letters to eligible first-degree family members of the probands. If we do not hear back from individual family members, we will follow-up with another letter, telephone call, or home visit. The information contained in the letters will be the same information for both the direct and indirect arms of the study. All interested family members will receive pre-test counseling and free, in-home, saliva-based genetic testing, and post-test counseling.