Resources Repository
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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…
Probability/Bayes | Test Performance | Health/Medicine | Technology Assessment | Infectious Diseases | Clinical Care -
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…
Probability/Bayes | Test Performance | Health/Medicine | Infectious Diseases | Clinical Care -
ArticlePublication 2020Interpreting COVID-19 Test Results: A Bayesian Approach
This article considers the following question with respect to interpreting the results of polymerase chain reaction …
This article considers the following question with respect to interpreting the results of polymerase chain reaction (PCR) assays from nasal and pharyngeal swabs for COVID-19 to inform clinical decision making: "While a positive result in an acutely ill patient is straightforward, how should physicians interpret negative tests in patients with suspected COVID-19 infection?" Using an assumption of near-perfect specificity of PCR assays for COVID-19, the authors acknowledge the uncertainty of test sensitivity. They consider two clinical scenarios…
Probability/Bayes | Test Performance | Health/Medicine | Infectious Diseases | Science/Technology | Global -
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…
Probability/Bayes | Test Performance | Health/Medicine | Clinical Care -
ReviewPublication 2021Review of Web-Based Tools for Value-of-Information Analysis
Value-of-information analysis (VOI) is an analytic approach used to inform research priorities, guide clinical trial …
Value-of-information analysis (VOI) is an analytic approach used to inform research priorities, guide clinical trial design, and provide information for decisions about reimbursement. The authors review existing web-based tools to facilitate VOI calculations. These include Sheffield Accelerated Value of Information (SAVI), the web interface to the BCEA (Bayesian Cost-Effectiveness Analysis) R package (BCEAweb), Rapid Assessment of Need for Evidence (RANE), and Value of Information for Cardiovascular Trials and Other Comparative Research (VICTOR).
Priority Setting/Ethics | Health/Medicine | Decision Theory | Value of Information | Cost-Effectiveness Analysis | Economics/Finance -
ArticlePublication 2008Cost-Effectiveness of Rapid Point-of-Care Prenatal Syphilis Screening in Sub-Saharan Africa
This paper investigates the cost-effectiveness of using rapid point-of-care tests for prenatal syphilis screening among …
This paper investigates the cost-effectiveness of using rapid point-of-care tests for prenatal syphilis screening among pregnant women in sub-Saharan Africa, a region with syphilis prevalence rates as high as 17%, and where traditional multi-test screening methods have been challenging to implement. Focusing on newly available rapid point-of-care screening tests, strategies differed by the initial test [rapid plasma reagin (RPR), immunochromographic strip (ICS)], need for confirmation with Treponema pallidum hemagglutination assay, and number of visits required.…
Test Performance | Health/Medicine | Costing Methods | Mathematical Models | Cost-Effectiveness Analysis | Technology Assessment | Infectious Diseases | Maternal/Reproductive Health | Clinical Care | Sub-Saharan Africa -
ArticlePublication 2023Performance of Rapid Antigen Tests to Detect Symptomatic and Asymptomatic SARS-CoV-2 Infection
The objective of this study was to evaluate the performance of rapid antigen tests (Ag-RDTs) …
The objective of this study was to evaluate the performance of rapid antigen tests (Ag-RDTs) for detection of SARS-CoV-2 among symptomatic and asymptomatic participants. The general findings were that the performance of Ag-RDTs was optimized when asymptomatic participants tested 3 times at 48-hour intervals and when symptomatic participants tested 2 times separated by 48 hours. Participants completed Ag-RDTs and reverse transcriptase polymerase chain reaction (RT-PCR) testing for SARS-CoV-2 every 48 hours for 15 days. They…
Test Performance | Health/Medicine | Infectious Diseases | Clinical Care | Science/Technology | North America -
ArticlePublication 2020Variation in False-Negative Rate of Reverse Transcriptase Polymerase Chain Reaction-Based SARS-CoV-2 Tests by Time Since Exposure
This study aimed to determine the false-negative rate of RT-PCR tests for SARS-CoV-2 infection based …
This study aimed to determine the false-negative rate of RT-PCR tests for SARS-CoV-2 infection based on the timeline of exposure and symptom onset. Drawing from data in seven studies involving 1,330 upper respiratory tract samples, a Bayesian model was used to estimate these rates. Findings showed that in the initial four days prior to typical symptom onset, the false-negative rate decreased from 100% on day 1 to 67% on day 4. By the day of…
Test Performance | Health/Medicine | Infectious Diseases | Clinical Care | Science/Technology | North America -
ReviewPublication 2021Considerations for Diagnostic COVID-19 Tests
During the initial stages of the COVID-19 pandemic, there was a rush by numerous diagnostic …
During the initial stages of the COVID-19 pandemic, there was a rush by numerous diagnostic test manufacturers to create, validate, and implement testing methods. This review discusses the pivotal role of diagnostic tests during the pandemic's first global wave, highlighting the challenges in technology and implementation experienced early on. The study also offers insights for enhancing the use of diagnostics, especially syndromic ones, should there be future spikes or regional outbreaks of COVID-19. The overarching…
Test Performance | Health/Medicine | Infectious Diseases | Clinical Care | Science/Technology | North America