23 research outputs found
Cost-effectiveness of a multitarget stool DNA test for colorectal cancer screening of Medicare beneficiaries
Background
In 2014, the Centers for Medicare and Medicaid Services (CMS) began covering a multitarget stool DNA (mtSDNA) test for colorectal cancer (CRC) screening of Medicare beneficiaries. In this study, we evaluate
Cost-Effectiveness of Risk-Stratified Colorectal Cancer Screening Based on Polygenic Risk: Current Status and Future Potential
Background: Although uniform colonoscopy screening reduces colorectal cancer (CRC) mortality, risk-based screening may
be more efficient. We investigated whether CRC screening based on polygenic risk is a cost-effective alternative to current
uniform screening, and if not, under what conditions it would be.
Methods: The MISCAN-Colon model was used to simulate a hypothetical cohort of US 40-year-olds. Uniform
screening was modeled as colonoscopy screening at ages 50, 60, and 70 years. For risk-stratified screening, individuals
underwent polygenic testing with current and potential future discriminatory performance (area under the receiveroperating curve [AUC] of 0.60 and 0.65–0.80, respectively). Polygenic testing results were used to create risk groups, for
which colonoscopy screening was optimized by varying the start age (40–60 years), en
Developing 1D nanostructure arrays for future nanophotonics
There is intense and growing interest in one-dimensional (1-D) nanostructures from the perspective of their synthesis and unique properties, especially with respect to their excellent optical response and an ability to form heterostructures. This review discusses alternative approaches to preparation and organization of such structures, and their potential properties. In particular, molecular-scale printing is highlighted as a method for creating organized pre-cursor structure for locating nanowires, as well as vapor–liquid–solid (VLS) templated growth using nano-channel alumina (NCA), and deposition of 1-D structures with glancing angle deposition (GLAD). As regards novel optical properties, we discuss as an example, finite size photonic crystal cavity structures formed from such nanostructure arrays possessing highQand small mode volume, and being ideal for developing future nanolasers
Exercise echocardiography or exercise SPECT imaging? - a meta-analysis of diagnostic test performance
Context.-Cardiac imaging has advanced rapidly, providing clinicians with several choices for evaluating patients with suspected coronary artery disease, but few studies compare modalities directly. .-To review the contemporary literature and to compare the diagnostic performance of exercise echocardiography (ECHO) and exercise single-photon emission computed tomography (SPECT) imaging in the diagnosis of coronary artery disease. Data Sources.-Studies published between January 1990 and October 1997 identified from MEDLINE search; bibliographies of reviews and original articles; and suggestions from experts in each area. Study Selection.-Articles were included if they discussed exercise ECHO and/or exercise SPECT imaging with thallous chloride TI 201 (thallium)or technetium Tc 99m sestamibi for detection and/or evaluation of coronary artery disease, if data on coronary angiography were presented as the reference test, and if the absolute numbers of true-positive, false-negative, true-negative, and false-positive observations were available or derivable from the data presented. Studies performed exclusively in patients after myocardia infarction, after percutaneous transluminal coronary angioplasty, after coronary artery bypass grafting, or with recent unstable coronary syndromes were excluded. Data Extraction.-ClinicaI variables, technical factors, and test performance were independently extracted by 2 reviewers on a standardized spreadsheet. Discrepancies were resolved by consensus. Results.-Forty-four articles met inclusion criteria. in pooled data weighted by the sample size of each study, exercise ECHO had a sensitivity of 85% (95% confidence interval [CI], 83%-87%) with a specificity of 77% (95% CI, 74%-80%). Exercise SPECT yielded a similar sensitivity of 87% (95% CI, 86%-88%) but a lower specificity of 64% (95% CI, 60%-68%), In a summary receiver operating characteristic model comparing exercise ECHO performance to exercise SPECT, exercise ECHO was associated with significantly better discriminatory power (parameter estimate, 1.18; 95% CI, 0.71-1.65), when adjusted for age, publication year, and a setting including known coronary artery disease for SP ECT studies. In models comparing the discriminatory abilities of exercise ECHO and exercise SPECT vs exercise testing without imaging, both ECHO and SPECT performed significantly better than exercise testing. The incremental improvement in performance was greater for ECHO (3.43; 95% CI, 2.74-4.11) than for SPECT (1.49; 95% CI, 0.91-2.08). Conclusions.-Exercise ECHO and exercise SPECT have similar sensitivities for the detection of coronary artery disease, but exercise ECHO has better specificity and, therefore, higher overall discriminatory capabilities as used in contemporary practice
Clarifying differences in natural history between models of screening: The case of colorectal cancer
Background. Microsimulation models are important decision support tools for screening. However, their complexity makes them difficult to understand and limits realization of their full potential. Therefore, it is important to develop documentation that clarifies their structure and assumptions. The authors demonstrate this problem and explore a solution for natural history using 3 independently developed colorectal cancer screening models. Methods. The authors first project effectiveness and cost-effectiveness of colonoscopy screening for the 3 models (CRC-SPIN, SimCRC, and MISCAN). Next, they provide a conventional presentation of each model, including information on structure and parameter values. Finally, they report the sim