The Experts below are selected from a list of 26418 Experts worldwide ranked by ideXlab platform
K J Rothman - One of the best experts on this subject based on the ideXlab platform.
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Methodologic frontiers in Environmental Epidemiology.
Environmental health perspectives, 1993Co-Authors: K J RothmanAbstract:Environmental Epidemiology comprises the epidemiologic study of those Environmental factors that are outside the immediate control of the individual. Exposures of interest to Environmental epidemiologists include air pollution, water pollution, occupational exposure to physical and chemical agents, as well as psychosocial elements of Environmental concern. The main methodologic problem in Environmental Epidemiology is exposure assessment, a problem that extends through all of epidemiologic research but looms as a towering obstacle in Environmental Epidemiology. One of the most promising developments in improving exposure assessment in Environmental Epidemiology is to find exposure biomarkers, which could serve as built-in dosimeters that reflect the biologic footprint left behind by Environmental exposures. Beyond exposure assessment, epidemiologists studying Environmental exposures face the difficulty of studying small effects that may be distorted by confounding that eludes easy control. This challenge may prompt reliance on new study designs, such as two-stage designs in which exposure and disease information are collected in the first stage, and covariate information is collected on a subset of subjects in state two. While the analytic methods already available for Environmental Epidemiology are powerful, analytic methods for ecologic studies need further development. This workshop outlines the range of methodologic issues that Environmental epidemiologists must address so that their work meets the goals set by scientists and society at large.
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Methodologic Frontiers in Environmental Epidemiology
Environmental Health Perspectives, 1993Co-Authors: K J RothmanAbstract:Environmental Epidemiology comprises the epidemiologic study of those Environmental factors that are outside the immediate control of the individual. Exposures of interest to Environmental epidemio...
Duncan Thomas - One of the best experts on this subject based on the ideXlab platform.
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Principles of study design in Environmental Epidemiology.
Environmental Health Perspectives, 1993Co-Authors: Hal Morgenstern, Duncan ThomasAbstract:This paper discusses the principles of study design and related methodologic issues in Environmental Epidemiology. Emphasis is given to studies aimed at evaluating causal hypotheses regarding expos...
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MEASUREMENT ISSUES IN Environmental Epidemiology
Environmental Health Perspectives, 1993Co-Authors: Maureen Hatch, Duncan ThomasAbstract:This paper deals with the area of Environmental Epidemiology involving measurement of exposure and dose, health outcomes, and important confounding and modifying variables (including genotype and psychosocial factors). Using examples, we illustrate strategies for increasing the accuracy of exposure and dose measurement that include dosimetry algorithms, pharmacokinetic models, biologic markers, and use of multiple measures. Some limitations of these methods are described and suggestions are made about where formal evaluation might be helpful. We go on to discuss methods for assessing the inaccuracies in exposure or dose measurements, including sensitivity analysis and validation studies. In relation to measurement of health outcomes, we discuss some definitional issues and cover, among other topics, biologic effect markers and other early indicators of disease. Because measurement error in covariates is also important, we consider the problems in measurement of common confounders and effect modifiers. Finally, we cite some general methodologic research needs.
I C Mills - One of the best experts on this subject based on the ideXlab platform.
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Environmental Epidemiology study methods and application
Occupational and Environmental Medicine, 2009Co-Authors: I C MillsAbstract:Edited by Dean Baker, Mark J Nieuwenhuijsen. Published by Oxford University Press, Oxford, 2008 pp 398. £34.95 (paperback). 978-0-19-852792-3 As a young scientist working and pursuing a PhD in the field of air pollution Epidemiology I thought that I fit the target readership of this book and was pleased to be asked to write a review. The preface indicates that the book will be of use to professionals dealing with Environmental hazards and those wishing to develop an interest in Environmental Epidemiology. In addition, it is targeted at “intermediate level courses in teaching programmes in public health, Epidemiology, and Environmental sciences”. Written and edited by distinguished researchers in the field, this 398-page book aims to “develop an understanding and knowledge of Environmental methods” with an “emphasis on methodological principles and good practice”. The book begins with a brief introduction to Environmental Epidemiology, illustrated by examples of classical studies in the field, such as John Snow’s investigation of London’s cholera epidemic in the nineteenth century and the London smog of 1952. This introductory chapter provides the reader with an understanding of why Environmental epidemiological studies are conducted and highlights the multidisciplinary nature of the subject. Following this is a review of the basic principles and terminology used in Epidemiology, and although the …
Ben Armstrong - One of the best experts on this subject based on the ideXlab platform.
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R code, Stata code and data for: "Time series regression studies in Environmental Epidemiology"
2017Co-Authors: Krishnan Bhaskaran, Antonio Gasparrini, Shakoor Hajat, Liam Smeeth, Ben ArmstrongAbstract:A tutorial on time series analysis applied to Environmental Epidemiology, with an example on the association of mortality with air pollution and temperature. The R code reproduces completely the example included in the accompanying article, illustrating the various analytical steps. Simple analyses with DLMs are also included, using functions in the R package dlnm. The material includes: [1] londondataset2002_2006.dta stores the dataset used in the illustrative examples in a Stata data format; [2] Rcode.R is the R code the reproduce the examples; [3] Statacode.do is the Stata code to reproduce the examples
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Analysis of time-stratified case-crossover studies in Environmental Epidemiology using Stata
2014Co-Authors: Aurelio Tobias, Ben Armstrong, Antonio GasparriniAbstract:The time-stratified case-crossover design is widely used in Environmental Epidemiology to analyze the short-term effects of Environmental risk factors, such as air pollution or temperature, on human health. It compares the exposure level in the day when the health event occurs (case day) with the levels in control days chosen with alternative selection methods. Standard analytical approaches to case-crossover analysis, based on conditional logistic regression (the clogit command in Stata), require a considerable amount of data management. Here we introduce the gencco command to reshape datasets from time-series to time-stratified case-crossover designs. Then we will discuss alternative statistical models to perform case-crossover analysis for aggregated data using Poisson and overdispersed Poisson regression (poisson and glm) and conditional Poisson regression (xtpoisson). Furthermore, we also introduce an updated command for conditional Poisson to allow for overdispersion (xtpoisson_addOD). Examples will be given using air pollution and mortality datasets, although these methods can be applicable generally in other contexts.
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Time series regression studies in Environmental Epidemiology
International journal of epidemiology, 2013Co-Authors: Krishnan Bhaskaran, Antonio Gasparrini, Shakoor Hajat, Liam Smeeth, Ben ArmstrongAbstract:Time series regression studies have been widely used in Environmental Epidemiology, notably in investigating the short-term associations between exposures such as air pollution, weather variables or pollen, and health outcomes such as mortality, myocardial infarction or disease-specific hospital admissions. Typically, for both exposure and outcome, data are available at regular time intervals (e.g. daily pollution levels and daily mortality counts) and the aim is to explore short-term associations between them. In this article, we describe the general features of time series data, and we outline the analysis process, beginning with descriptive analysis, then focusing on issues in time series regression that differ from other regression methods: modelling short-term fluctuations in the presence of seasonal and long-term patterns, dealing with time varying confounding factors and modelling delayed ('lagged') associations between exposure and outcome. We finish with advice on model checking and sensitivity analysis, and some common extensions to the basic model.
Paul Elliott - One of the best experts on this subject based on the ideXlab platform.
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geographical and Environmental Epidemiology methods for small area studies
Journal of the American Statistical Association, 1997Co-Authors: Karen Kafadar, Paul Elliott, Jack Cuzick, Dallas R English, R SternAbstract:Part 1 Introduction: geographihcal Epidemiology and ecological studies small-area studies - purpose and methods health and the environment - the significance of chemicals and radiation. Part 2 Data, computational methods and mapping: mortality data cancer incidence data for adults cancer incidence data for children congenital anomalies specialized registers population counts in small areas use of routine data in studies of point sources of Environmental pollution socio-economic confounding use of record linkage in small-area studies confidentiality practical approaches to disease mapping estimating Environmental exposures mapping Environmental exposure. Part 3 Statistical methods: statistical methods for geographical correlation studies Bayesian methods for mapping disease risk statistical methods for analyzing point-source exposures some comments on methods for investigating disease risk around a point source methods for the assessment of disease clusters. Part 4 Studies of health and the environment: Environmental Epidemiology - a historical perspective guidelines for the investigation of clusters of adverse health events studies of diseas clustering - problems of interpretation. Part 5 Case studies: childhood leukaemia around the Sellafield nuclear plant the epidemic of respiratory cancer associated with erionite fibres in the Cappadocian region of Turkey soya bean as a risk factor of epidemic asthma the Seveso accident cancer of the larynx and lung near incinerators of waste solvents and oils in Britain a study of geographical correlations in China.
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Spatial statistical methods in Environmental Epidemiology: a critique.
Statistical methods in medical research, 1995Co-Authors: Paul Elliott, Marco Martuzzi, Gavin ShaddickAbstract:Despite recent advances in the available statistical methods for geographical analysis, there are many constraints to their application in Environmental Epidemiology. These include problems of data availability and quality, especially the lack in most situations of Environmental exposure measurements. Methods for disease 'cluster' investigation, point source exposures, small-area disease mapping and ecological correlation studies are critically reviewed, with the emphasis on practical applications and epidemiological interpretation. It is shown that, unless dealing with rare diseases, high specificity exposures and high relative risks, cluster investigation is unlikely to be fruitful, and is often complicated by the post hoc nature of such studies. However, it is recognized that in these circumstances proper assessment of the available data is often required as part of the public health response. Newly availabe methods, particularly in Bayesian statistics, offer an appropriate framework for geographical a...