Resources Repository
-
ArticlePublication 2022Comparison of Home Antigen Testing With RT-PCR and Viral Culture During the Course of SARS-CoV-2 Infection
As the availability of at-home self-collected antigen tests for SARS-CoV-2 increases, understanding their efficacy is …
As the availability of at-home self-collected antigen tests for SARS-CoV-2 increases, understanding their efficacy is crucial. A study in San Diego and Denver between January and May 2021 assessed the reliability of these tests against standard RT-PCR tests and viral cultures. Of the 225 participants with confirmed infections, the antigen test sensitivity was found to be 50% during the infectious period, 64% against the same-day RT-PCR, and 84% against the same-day cultures. Sensitivity was highest…
Clinical Care | Test Performance | Infectious Diseases | Culture/Society | Health/Medicine | Science/Technology -
ReviewPublication 2022Diagnostics for COVID-19: Moving from Pandemic Response to Control
Diagnostics are essential in managing the COVID-19 pandemic, with three primary methods for detecting SARS-CoV-2 …
Diagnostics are essential in managing the COVID-19 pandemic, with three primary methods for detecting SARS-CoV-2 infections. Each test type remains vital as we shift from responding to controlling the pandemic. Molecular tests, like PCR, are highly precise in identifying viral RNA and are endorsed by the WHO for confirming cases and guiding public health actions. Antigen rapid tests spot viral proteins and, while less accurate than molecular tests, are quicker, more affordable, simpler, and can…
Clinical Care | Test Performance | Infectious Diseases | Health Systems | Health/Medicine | Science/Technology -
ArticlePublication 2020Testing for SARS-CoV-2 Antibodies
Antibody testing can determine previous exposure to SARS-CoV-2 virus. Recently, the UK government has made …
Antibody testing can determine previous exposure to SARS-CoV-2 virus. Recently, the UK government has made antibody testing available to anyone wanting it, even if there is no clinical indication. The purpose of this article is to provide guidance for when to consider antibody testing in individuals with and without symptoms suggestive of current or past SARS-CoV-2 infection. Key points made by the authors include: (1) antibody testing is likely to be most useful 2 weeks…
Clinical Care | Test Performance | Probability/Bayes | Technology Assessment | Infectious Diseases | Health/Medicine -
ToolInteractive 2020COVID-19 Antibody Tests: Calculator for Interpreting Test Results
Antibody testing can determine previous exposure to SARS-CoV-2 virus. This interactive calculator, linked to the article …
Antibody testing can determine previous exposure to SARS-CoV-2 virus. This interactive calculator, linked to the article below* on antibody testing for SARS-CoV-2 virus, allows users to vary the prior probability of infection, the sensitivity of SARS-CoV-2 antibody testing, and the specificity of SARS-CoV-2 antibody testing. Key points made in the article accompanying the interactive include: (1) antibody testing is likely to be most useful 2 weeks after infection, (2) sensitivity and specificity will vary over time and…
Clinical Care | Test Performance | Probability/Bayes | Technology Assessment | Infectious Diseases | Health/Medicine | Science/Technology -
ArticlePublication 2020Bayes' Theorem, COVID-19, and Screening Tests
This article reviews the implications of increased testing for COVID-19 using reverse transcriptase polymerase chain …
This article reviews the implications of increased testing for COVID-19 using reverse transcriptase polymerase chain reaction (rRT-PCR) through the application of Bayes’ Theorem for three hypothetical, stylized case scenarios. The scenarios involve three patients with a low, moderate, and high pre-test probability of COVID-19 infection. The category of low probability would include "asymptomatic individuals in a presumed low prevalence environment" and might vary from 10 to 20%. The category of moderate probability would include "individuals…
Clinical Care | Test Performance | Probability/Bayes | Infectious Diseases | Health/Medicine -
Tools/ModelsInteractive, Teaching Resource 2020Interactive Graphic: Interpreting a COVID-19 Test Result
Currently, the most common diagnostic test for COVID-19 relies on reverse transcriptase polymerase chain reaction …
Currently, the most common diagnostic test for COVID-19 relies on reverse transcriptase polymerase chain reaction (RT-PCR), and most often uses samples obtained from the respiratory tract by nasopharyngeal swab. This interactive graphic demonstrates the influence of the prior probability of COVID-19, the test sensitivity (i.e., the probability of a positive test conditional on disease presence), and the test specificity (i.e., the probability of a negative test conditional on disease absence) on the post-test probability of…
Clinical Care | Test Performance | Probability/Bayes | Infectious Diseases | Health/Medicine | Science/Technology | High School | College | Graduate | Doctoral | Professional | Graphics/Visualization | Quantitative Literacy -
ArticlePublication 2020Translating Population Evidence to Individual Patients
In this paper, the authors describe the differences in population level outcomes compared to individual …
In this paper, the authors describe the differences in population level outcomes compared to individual patients and discuss ways that these are differences. The authors cover topics including the difference between relative and absolute risk and benefit. They use an example of the decision to start anticoagulation in new-onset atrial fibrillation to discuss translating population level evidence to treatment of an individual. These options include generalizability, subgroup analysis, prediction rules, following response to therapy, and even…
Clinical Care | Test Performance | Evidence Synthesis | Health Systems | Health/Medicine -
ArticlePublication 2020Clinical Decision Making: Using a Diagnostic Test
This article is part of a 6-part series on clinical decision making. The authors use …
This article is part of a 6-part series on clinical decision making. The authors use two clinical examples to review the principles of interpreting diagnostic test results. They outline an approach that can be used to determine how to select and apply tests and their results to the practice of internal medicine. Topics covered in the two case studies include sensitivity and specificity, positive predictive and negative predictive value of tests, and how to estimate…
Clinical Care | Test Performance | Probability/Bayes | Health/Medicine -
ArticlePublication 2015A Conceptual Model for Breast, Cervical, and Colorectal Cancer Screening
General frameworks of the cancer screening process are available, but none directly compare the process …
General frameworks of the cancer screening process are available, but none directly compare the process in detail across different organ sites. This limits the ability of medical and public health professionals to develop and evaluate coordinated screening programs that apply resources and population management strategies available for one cancer site to other sites. This paper presents a conceptual model that incorporates a single screening episode for breast, cervical, and colorectal cancers into a unified framework based…
Clinical Care | Test Performance | Preferences/Values | Health Outcomes | Evidence Synthesis | Microsimulation | Cost-Effectiveness Analysis | Chronic Disease/Risk | Health Systems | Health/Medicine | Science/Technology | North America