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…
Infectious Diseases | Test Performance | Probability/Bayes | Technology Assessment | Clinical Care | Health/Medicine -
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…
Infectious Diseases | Test Performance | Probability/Bayes | Technology Assessment | Health Systems | Policy/Regulation | Government/Law | Health/Medicine | Global | North America -
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…
Infectious Diseases | Test Performance | Probability/Bayes | Clinical Care | Health/Medicine -
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…
Infectious Diseases | Test Performance | Probability/Bayes | Health/Medicine | Science/Technology | Global -
BookPublication 1980Clinical Decision Analysis
This text was conceived and developed in the Harvard T.H. Chan School of Public Health …
This text was conceived and developed in the Harvard T.H. Chan School of Public Health at the Center for the Analysis of Health Practices. The book had its origins in a set of classroom materials developed during the academic year 1974-75 for an elective course in medical decision making at the Harvard Medical School. In this book students are shown how to structure clinical decision problems, how to systematically formulate the intertwining roles of diagnosis and treatment, how to…
Infectious Diseases | Test Performance | Probability/Bayes | Preferences/Values | Costing Methods | Health Outcomes | Value of Information | State-Transition | Decision Analysis | Cost-Effectiveness Analysis | Child/Nutrition | Chronic Disease/Risk | Economics/Finance | Health/Medicine | Global | North America | Europe | Graduate | Doctoral | Critical Thinking/Analysis | Decision Making/Leadership | Quantitative Literacy -
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.…
Infectious Diseases | Test Performance | Costing Methods | Mathematical Models | Cost-Effectiveness Analysis | Technology Assessment | Maternal/Reproductive Health | Clinical Care | Health/Medicine | 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…
Infectious Diseases | Test Performance | Clinical Care | 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…
Infectious Diseases | Test Performance | Clinical Care | 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…
Infectious Diseases | Test Performance | Clinical Care | Health/Medicine | Science/Technology | North America