Resources Repository
-
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…
Test Performance | Clinical Care | 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…
Test Performance | Clinical Care | 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…
Test Performance | Clinical Care | Probability/Bayes | Infectious Diseases | Health/Medicine | Science/Technology | High School | College | Graduate | Doctoral | Professional | Graphics/Visualization | Quantitative Literacy -
ArticlePublication 2020Incorporating Perspective into Clinical Decisions
Part of a six-part series of articles on clinical decision making, in this article, the …
Part of a six-part series of articles on clinical decision making, in this article, the authors discuss how to incorporate perspective into clinical decisions, explicitly acknowledging that the treating physician is not the only stakeholder in these decisions. The authors use 2 case studies to demonstrate how changes in perspective can alter the clinical decision as well lead to both intended and unintended consequences to the outcomes.
Health Outcomes | Clinical Care | Preferences/Values | Priority Setting/Ethics | Health Systems | Health/Medicine -
ArticlePublication 2020Weighing Evidence to Inform Clinical Decisions
The authors use a clinical example to simulate how treatment discussions can be complicated when new evidence is introduced …
The authors use a clinical example to simulate how treatment discussions can be complicated when new evidence is introduced that conflicts with existing guidelines. Even when evidence is consistent, the authors point out that current guidelines can have interpretations that don't agree with available evidence. They develop a step-wise algorithm to help guide individual clinical decisions even in the absence of general consensus related to appropriate testing and treatment.
Evidence Synthesis | Clinical Care | Priority Setting/Ethics | 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…
Test Performance | Clinical Care | Probability/Bayes | Health/Medicine -
ArticlePublication 2019Cost-Effectiveness of Clinic, Home, or Ambulatory Blood Pressure Measurement for Hypertension Diagnosis
This study compared three methods of blood pressure (BP) measurement for diagnosing hypertension in primary …
This study compared three methods of blood pressure (BP) measurement for diagnosing hypertension in primary care settings, accounting for the possibility of false-positive (white-coat hypertension) and false-negative (masked hypertension) clinic measurements. Outcomes included quality-adjusted life years (QALYs) and lifetime costs associated with clinic BP measurement, home BP monitoring, and ambulatory blood pressure monitoring (ABPM) under two scenarios: positive and negative initial screening. Data were from published literature, public data sources, and expert input. In the…
Clinical Care | Mathematical Models | Cost-Effectiveness Analysis | Chronic Disease/Risk | Health/Medicine | North America -
ArticlePublication 2017Cost-Effectiveness of Screening for Hypertension and Counseling for Prevention
This article aimed to compare the health and economic impact of 3 services recommended by …
This article aimed to compare the health and economic impact of 3 services recommended by the US Preventive Services Task Force for the primary prevention of cardiovascular disease (CVD): (1) aspirin counseling for the primary prevention of CVD and colorectal cancer, (2) screening and treatment for lipid disorders (usually high cholesterol), and (3) screening and treatment for hypertension. A microsimulation model was used to compare lifetime outcomes from the societal perspective for a US-representative birth…
Clinical Care | Microsimulation | Cost-Effectiveness Analysis | Chronic Disease/Risk | Policy/Regulation | Health/Medicine | North America -
ArticlePublication 2017Costs of Facility-Based HIV Testing in Malawi, Zambia and Zimbabwe
Providing HIV testing at health facilities remains the most common approach to ensuring access to …
Providing HIV testing at health facilities remains the most common approach to ensuring access to HIV treatment and prevention services for the millions of undiagnosed HIV-infected individuals in sub-Saharan Africa. The authors sought to explore the costs of providing these services across three southern African countries with high HIV burden.Primary costing studies were undertaken in 54 health facilities providing HIV testing services (HTS) in Malawi, Zambia and Zimbabwe. Routinely collected monitoring and evaluation data for…
Costing Methods | Clinical Care | Technology Assessment | Infectious Diseases | Health Systems | Health/Medicine | Sub-Saharan Africa