PurposeClinical next generation sequencing (CNGS) is introducing new opportunities and challenges into the practice of medicine. Simultaneously, these technologies are generating uncertainties of unprecedented scale that laboratories, clinicians, and patients are required to address and manage. We describe in this report the conceptual design of a new taxonomy of uncertainties around the use of CNGS in health care.MethodsInterviews to delineate the dimensions of uncertainty in CNGS were conducted with genomics experts, and themes were extracted in order to expand upon a previously published three-dimensional taxonomy of medical uncertainty. In parallel we developed an interactive website to disseminate the CNGS taxonomy to researchers and engage them in its continued refinement.ResultsThe proposed taxonomy divides uncertainty along three axes: source, issue, and locus, and further discriminates the uncertainties into five layers with multiple domains. Using a hypothetical clinical example, we illustrate how the taxonomy can be applied to findings from CNGS and used to guide stakeholders through interpretation and implementation of variant results.ConclusionThe utility of the proposed taxonomy lies in promoting consistency in describing dimensions of uncertainty in publications and presentations, to facilitate research design and management of the uncertainties inherent in the implementation of CNGS.

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Background Conventional multi-session genetic counseling is currently recommended when disclosing APOE genotype for risk of Alzheimer’s disease (AD) in cognitively normal individuals. Objective To evaluate the safety of brief disclosure protocols for disclosing APOE genotype for risk of Alzheimer’s disease (AD). Methods A randomized, multicenter non-inferiority trial was conducted at 4 sites. Participants were asymptomatic adults having a first-degree relative with AD. A standard disclosure protocol by genetic counselors (SP-GC) was compared to condensed protocols, with disclosures by genetic counselors (CP-GC) and by physicians (CP-MD). Pre-planned co-primary outcomes were anxiety and depression scales 12 months after disclosure. Results 343 adults (mean age 58.3, range 33–86 years, 71% female, 23% African American) were randomly assigned to the SP-GC protocol (n= 115), CP-GC protocol (n=116) or CP-MD protocol (n=112). Mean post-disclosure scores on all outcomes were well below cut-offs for clinical concern across protocols. Comparing CP-GC to SP-GC, the 97.5% upper confidence limits at 12 months after disclosure on co-primary outcomes of anxiety and depression ranged from a difference of 1.2 to 2.0 in means (all p<0.001 on non-inferiority tests), establishing non-inferiority for condensed protocols. Results were similar between European Americans and African Americans. Conclusions These data support the safety of condensed protocols for APOE disclosure for those free of severe anxiety or depression who are actively seeking such information.

Background: We sought to identify optimal approaches by calibrating longitudinal cognitive performance across studies with different neuropsychological batteries. Methods: We examined four approaches to calibrate cognitive performance in nine longitudinal studies of Alzheimer's disease (AD) (n = 10,875): (1) common test, (2) standardize and average available tests, (3) confirmatory factor analysis (CFA) with continuous indicators, and (4) CFA with categorical indicators. To compare precision, we determined the minimum sample sizes needed to detect 25% cognitive decline with 80% power. To compare criterion validity, we correlated cognitive change from each approach with 6-year changes in average cortical thickness and hippocampal volume using available MRI data from the AD Neuroimaging Initiative. Results: CFA with categorical indicators required the smallest sample size to detect 25% cognitive decline with 80% power (n = 232) compared to common test (n = 277), standardize-and-average (n = 291), and CFA with continuous indicators (n = 315) approaches. Associations with changes in biomarkers changes were the strongest for CFA with categorical indicators. Conclusions: CFA with categorical indicators demonstrated greater power to detect change and superior criterion validity compared to other approaches. It has wide applicability to directly compare cognitive performance across studies, making it a good way to obtain operational phenotypes for genetic analyses of cognitive decline among people with AD. i 2014 S. Karger AG, Basel