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 | Technology Assessment | Clinical Care | 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…
Probability/Bayes | Test Performance | Technology Assessment | Clinical Care | Infectious Diseases | Health/Medicine | Science/Technology -
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 | Technology Assessment | Clinical Care | Infectious Diseases | Costing Methods | Mathematical Models | Cost-Effectiveness Analysis | Maternal/Reproductive Health | Health/Medicine | Sub-Saharan Africa -
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 | Clinical Care | 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…
Probability/Bayes | Test Performance | Clinical Care | Infectious Diseases | Health/Medicine | Science/Technology | High School | College | Graduate | Doctoral | Professional | Graphics/Visualization | Quantitative Literacy -
EditorialPublication 2020Waiting for Certainty on COVID-19 Antibody Tests — At What Cost?
This perspective anticipates the availability of serologic antibody testing and considers its potential usefulness in mitigation …
This perspective anticipates the availability of serologic antibody testing and considers its potential usefulness in mitigation policy to reduce COVID-19 transmission. For example: Could we screen for serologic antibodies as a proxy for possible immunity and identify people who could return to the workplace with less severe mitigation measures? The authors acknowledge the uncertainties raised by many policy actors, including the WHO, such as, "Do antibodies confer immunity and, if so, for how long? How accurate is…
Probability/Bayes | Test Performance | Technology Assessment | Infectious Diseases | Health Systems | Policy/Regulation | Government/Law | Health/Medicine | Global | North America -
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 | Clinical Care | Infectious Diseases | Health/Medicine | 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 | Clinical Care | Infectious Diseases | Health/Medicine | 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 | Clinical Care | Infectious Diseases | Health/Medicine | Science/Technology | North America