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Medical Biomathematics and Biometrics Commons™
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Full-Text Articles in Medical Biomathematics and Biometrics
Software To Forecast The Global Burden Of Alzheimer's Disease, Ron Brookmeyer, Elizabeth Johnson, Kathryn Ziegler-Graham, H. Michael Arrighi
Software To Forecast The Global Burden Of Alzheimer's Disease, Ron Brookmeyer, Elizabeth Johnson, Kathryn Ziegler-Graham, H. Michael Arrighi
Ron Brookmeyer
Software was developed to forecast the global burden of Alzheimer’s disease and evaluate the potential impact of interventions that delay disease onset and progression. The output includes 50 year projections of Alzheimer's disease prevalence by stage of disease and region of the world. The methods are based on a stochastic multi-state model The software incorporates U.N. worldwide population forecasts and data from epidemiological studies on risks of Alzheimer’s disease. The user can also supply their own population projections, and modify input parameters for the model including the disease incidence rates, effects of interventions on disease onset and progression, and stages …
Confidence Intervals For Biomarker-Based Human Immunodeficiecny Virus Incidence Estimates And Differences Using Prevalent Data, Ron Brookmeyer, S Cole, H Chu
Confidence Intervals For Biomarker-Based Human Immunodeficiecny Virus Incidence Estimates And Differences Using Prevalent Data, Ron Brookmeyer, S Cole, H Chu
Ron Brookmeyer
Prevalent biological specimens can be used to estimate human immunodeficiency virus (HIV) incidence using a two-stage immunologic testing algorithm that hinges on the average time, say T, between testing HIV positive on highly and less sensitive enzyme immunoassays. Common approaches to confidence interval (CI) estimation for this incidence measure have included (1) ignoring the random error in T or (2) employing a Bonferroni adjustment to the box method. The authors present alternative Monte Carlo-based CIs for this incidence measure, as well as CIs for the biomarker-based incidence difference; standard approaches to CIs are typically appropriate for the incidence ratio. Using …
Modeling The Effect Of Alzheimer's Disease On Mortality, Elizabeth Johnson, Ron Brookmeyer, Kathryn Ziegler-Graham
Modeling The Effect Of Alzheimer's Disease On Mortality, Elizabeth Johnson, Ron Brookmeyer, Kathryn Ziegler-Graham
Ron Brookmeyer
Mortality rate ratios and the associated proportional hazards models have been used to summarize the effect of Alzheimer's disease on longevity. However, the mortality rate ratios vary by age and therefore do not provide a simple parsimonious summary of the effect of the disease on lifespan. Instead, we propose a new parameter that is defined by an additive multistate model. The proposed multistate model accounts for different stages of disease progression. The underlying assumption of the model is that the effect of disease on mortality is to add a constant amount to death rates once the disease progresses from an …