Resources Repository
-
ArticlePublication 2017Likelihood Approach for Calibration of Stochastic Epidemic Models
Stochastic transmission dynamic models are especially useful for studying the early emergence of novel pathogens …
Stochastic transmission dynamic models are especially useful for studying the early emergence of novel pathogens given the importance of chance events when the number of infectious individuals is small. However, methods for parameter estimation and prediction for these types of stochastic models remain limited. This paper describes a calibration and prediction framework for stochastic compartmental transmission models of epidemics. The proposed method applies a linear noise approximation to describe the size of the fluctuations, and…
Calibration/Validation | Dynamic Transmission | Infectious Diseases | Dynamic Simulation | Health Systems | Health/Medicine | Global -
ArticlePublication 2009Cost Effectiveness Analysis of Including Boys in a HPV Vaccination Program in the U.S.
This article reports on a societal-perspective cost effectiveness analysis of including preadolescent boys in a …
This article reports on a societal-perspective cost effectiveness analysis of including preadolescent boys in a routine human papillomavirus (HPV) vaccination program for preadolescent girls. The analysis included girls and boys aged 12 years; interventions included HPV vaccination of girls alone and of girls and boys in the context of screening for cervical cancer. The authors found that with 75% vaccination coverage and an assumption of complete, lifelong vaccine efficacy, routine HPV vaccination of 12-year-old girls…
Calibration/Validation | Dynamic Transmission | Infectious Diseases | Microsimulation | Cost-Effectiveness Analysis | Chronic Disease/Risk | Clinical Care | Economics/Finance | Health/Medicine | North America -
ArticlePublication 2008Health and Economic Implications of HPV Vaccination in the U.S.
This article reports on a study using models of HPV-16 and HPV-18 transmission and cervical …
This article reports on a study using models of HPV-16 and HPV-18 transmission and cervical carcinogenesis to compare the health and economic outcomes of vaccinating preadolescent girls in the US (at 12 years of age), and vaccinating older girls and women in catch-up programs (to 18, 21, or 26 years of age). The study also examined the health benefits of averting other HPV-16-related and HPV-18-related cancers, the prevention of HPV-6-related and HPV-11-related genital warts and…
Calibration/Validation | Dynamic Transmission | Infectious Diseases | Microsimulation | Cost-Effectiveness Analysis | Chronic Disease/Risk | Health Systems | Clinical Care | Economics/Finance | Health/Medicine | Science/Technology | North America -
ArticlePublication 2021New Microsimulation Models to Inform Cervical Cancer Control
Health decision models consider the lifetime natural history of human papillomavirus (HPV) infection and pathogenesis …
Health decision models consider the lifetime natural history of human papillomavirus (HPV) infection and pathogenesis of cervical cancer, and estimate the long-term impact of preventive interventions. We propose a new health decision modeling framework that de-emphasizes previously used cytologic-colposcopic-histologic diagnoses, which are subjective and lack reproducibility, relying instead on HPV type and duration of infection as the major determinants of model transition probabilities. We posit that new model health states and corollary transitions are universal,…
Calibration/Validation | Infectious Diseases | Mathematical Models | Microsimulation | Decision Analysis | Cost-Effectiveness Analysis | Global -
ArticlePublication 2021Impact of COVID-19 on Cancer Diagnosis and Survival in Chile
This paper estimates the impact of the COVID-19 pandemic on delays in cancer diagnosis in …
This paper estimates the impact of the COVID-19 pandemic on delays in cancer diagnosis in Chile, using a microsimulation model of five cancers: breast, cervix, colorectal, prostate, and stomach. The model simulates cancer incidence and progression, as well as stage-specific cancer detection and survival probabilities, and was calibrated to empirical data on monthly detected cases, stage at diagnosis, and 5-year net survival. The analysis accounted for the impact of COVID-19 on month-by-month excess mortality and…
Calibration/Validation | Infectious Diseases | Health Outcomes | Microsimulation | Chronic Disease/Risk | Latin America & Caribbean -
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 | Infectious Diseases | Test Performance | Technology Assessment | Clinical Care | Health/Medicine -
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 | Infectious Diseases | Test Performance | 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…
Probability/Bayes | Infectious Diseases | Test Performance | Health/Medicine | Science/Technology | Global -
ArticleWeb Portal 2017PLoS Collection: Prevention, Diagnosis and Treatment of Sexually Transmitted Infections
Globally, the World Health Organization (WHO) estimates that more than one million new sexually transmitted …
Globally, the World Health Organization (WHO) estimates that more than one million new sexually transmitted infections (STIs) occur each day, incurring a very substantial burden of morbidity, mortality and additional infections. The pathogens responsible include bacteria, parasites and viruses, and intensive research is needed to address the substantial barriers to diagnosis and treatment of STIs, and the behavioral challenges of prevention. This PLOS collection, published in collaboration with WHO, focuses on global policy and systems…
Dynamic Transmission | Infectious Diseases | Priority Setting/Ethics | Costing Methods | Mathematical Models | Cost-Effectiveness Analysis | Health Systems | Economics/Finance | Health/Medicine | Sub-Saharan Africa | Middle East & North Africa | Latin America & Caribbean | Asia & Pacific