Spatial-temporal modeling of the association between air pollution exposure and preterm birth: identifying critical windows of exposure.

abstract：:In genetic family studies, ages at onset of diseases are routinely collected. Often one is interested in assessing the familial association of ages at the onset of a certain disease type. However, when a competing risk is present and is related to the disease of interest, the usual measure of association by treating t...

journal_title：Biometrics

authors： Shih JH,Albert PS

更新日期：2010-12-01 00:00:00

abstract：:We consider inference for the reaction rates in discretely observed networks such as those found in models for systems biology, population ecology, and epidemics. Most such networks are neither slow enough nor small enough for inference via the true state-dependent Markov jump process to be feasible. Typically, infere...

journal_title：Biometrics

authors： Fearnhead P,Giagos V,Sherlock C

更新日期：2014-06-01 00:00:00

abstract：:In longitudinal observational studies, repeated measures are often taken at informative observation times. Also, there may exist a dependent terminal event such as death that stops the follow-up. For example, patients in poorer health are more likely to seek medical treatment and their medical cost for each visit tend...

journal_title：Biometrics

authors： Liu L,Huang X,O'Quigley J

更新日期：2008-09-01 00:00:00

abstract：:Many techniques of functional data analysis require choosing a measure of distance between functions, with the most common choice being L2 distance. In this article we show that using a weighted L2 distance, with a judiciously chosen weight function, can improve the performance of various statistical methods for funct...

journal_title：Biometrics

authors： Chen H,Reiss PT,Tarpey T

更新日期：2014-09-01 00:00:00

abstract：:In biostatistical practice, it is common to use information criteria as a guide for model selection. We propose new versions of the focused information criterion (FIC) for variable selection in logistic regression. The FIC gives, depending on the quantity to be estimated, possibly different sets of selected variables....

journal_title：Biometrics

authors： Claeskens G,Croux C,Van Kerckhoven J

更新日期：2006-12-01 00:00:00

abstract：:Understanding HIV incidence, the rate at which new infections occur in populations, is critical for tracking and surveillance of the epidemic. In this article, we derive methods for determining sample sizes for cross-sectional surveys to estimate incidence with sufficient precision. We further show how to specify samp...

journal_title：Biometrics

authors： Konikoff J,Brookmeyer R

更新日期：2015-12-01 00:00:00

abstract：:We describe group sequential tests for a bivariate response. The tests are defined in terms of the two response components jointly, rather than through a single summary statistic. Such methods are appropriate when the two responses concern different aspects of a treatment; for example, one might wish to show that a ne...

journal_title：Biometrics

authors： Jennison C,Turnbull BW

更新日期：1993-09-01 00:00:00

abstract：:A transformed Bernstein polynomial that is centered at standard parametric families, such as Weibull or log-logistic, is proposed for use in the accelerated hazards model. This class provides a convenient way towards creating a Bayesian nonparametric prior for smooth densities, blending the merits of parametric and no...

journal_title：Biometrics

authors： Chen Y,Hanson T,Zhang J

更新日期：2014-03-01 00:00:00

abstract：:This paper proposes a generalized estimating equations approach for the analysis of spatially correlated binary data when there are large numbers of spatially correlated observations on a moderate number of subjects. This approach is useful when the scientific focus is on modeling the marginal mean structure. Proper m...

journal_title：Biometrics

authors： Albert PS,McShane LM

更新日期：1995-06-01 00:00:00

abstract：:We propose a generalized linear mixed model to estimate and test marginal effects on titers repeatedly measured by serial dilution assays. The link is log-log and the titer is assumed to follow a gamma distribution. The parameters are estimated by generalized estimating equations. The marginal effects are tested by me...

journal_title：Biometrics

authors： Bloch J,Chavance M

更新日期：1998-06-01 00:00:00

abstract：:This paper establishes a framework for understanding the complex relationships between HIV-1 genotypic markers of resistance to antiretroviral drugs and clinical measures of disease progression. A new classification scheme based on the probabilities of how new patients will respond to antiretroviral therapy given the ...

journal_title：Biometrics

authors： Foulkes AS,De GV

更新日期：2002-03-01 00:00:00

abstract：:In epidemiologic studies of time to an event, mean lifetime is often of direct interest. We propose methods to estimate group- (e.g., treatment-) specific differences in restricted mean lifetime for studies where treatment is not randomized and lifetimes are subject to both dependent and independent censoring. The pro...

journal_title：Biometrics

authors： Zhang M,Schaubel DE

更新日期：2011-09-01 00:00:00

abstract：:Combined maximum likelihood estimates for equicorrelation covariance matrices are considered. The case of a common equicorrelation rho and possibly different standard deviations sigma 1, ..., sigma k among k experimental groups is examined first, and the estimation of (rho, sigma 1, ..., sigma k) is discussed. Second,...

journal_title：Biometrics

authors： Viana MA

更新日期：1994-09-01 00:00:00

abstract：:Many statistical tests have been proposed for case-control data to detect disease association with multiple single nucleotide polymorphisms (SNPs) in linkage disequilibrium. The main reason for the existence of so many tests is that each test aims to detect one or two aspects of many possible distributional difference...

journal_title：Biometrics

authors： Han F,Pan W

更新日期：2012-03-01 00:00:00

abstract：:We propose a nonparametric Bayesian approach to estimate the natural direct and indirect effects through a mediator in the setting of a continuous mediator and a binary response. Several conditional independence assumptions are introduced (with corresponding sensitivity parameters) to make these effects identifiable f...

journal_title：Biometrics

authors： Daniels MJ,Roy JA,Kim C,Hogan JW,Perri MG

更新日期：2012-12-01 00:00:00

abstract：:Jolliffe and Jolliffe (1997, Biometrics 53, 1136-1142) proposed various models for data from an experiment on memory in coal tits. This article describes an alternative model, which fits equally well and which may be simpler to interpret. ...

journal_title：Biometrics

authors： Ridout MS

更新日期：1999-06-01 00:00:00

abstract：:Three properties of interest in bioavailability studies using compartmental models are the area under the concentration curve, the maximum concentration, and the time to maximum concentration. Methods are described for finding designs that minimize the variance of the estimates of these quantities in such a model. The...

journal_title：Biometrics

authors： Atkinson AC,Chaloner K,Herzberg AM,Juritz J

更新日期：1993-06-01 00:00:00

abstract：:We study the issue of identifiability of mixture models in the context of capture-recapture abundance estimation for closed populations. Such models are used to take account of individual heterogeneity in capture probabilities, but their validity was recently questioned by Link (2003, Biometrics 59, 1123-1130) on the ...

journal_title：Biometrics

authors： Holzmann H,Munk A,Zucchini W

更新日期：2006-09-01 00:00:00

abstract：:The basic technical facts of human cytogenetics and the laboratory methods employed in chromosome research are explained in simple terms. The main variables used to describe chromosome images are defined and discussed. Three discriminant analysis models for chromosome classification are developed: one in which each ch...

journal_title：Biometrics

authors： Habbema JD

更新日期：1979-03-01 00:00:00

abstract：:Spatial data have become increasingly common in epidemiology and public health research thanks to advances in GIS (Geographic Information Systems) technology. In health research, for example, it is common for epidemiologists to incorporate geographically indexed data into their studies. In practice, however, the spati...

journal_title：Biometrics

authors： Huque MH,Bondell HD,Carroll RJ,Ryan LM

更新日期：2016-09-01 00:00:00

abstract：:A study of otitis media that requires a test for the comparison of two clustered samples of censored data is described. A method is proposed taking into account the within-subject correlation in the formation of the log-rank statistic. ...

journal_title：Biometrics

authors： Le CT,Lindgren BR

更新日期：1996-03-01 00:00:00

abstract：:In this study we are concerned with the construction of confidence intervals for the conditional probability of misallocation associated with Anderson's classification statistics, W. The available methods of computing confidence intervals for the conditional probability are not satisfactory in practice, mainly because...

journal_title：Biometrics

authors： McLachlan GJ

更新日期：1975-03-01 00:00:00

abstract：:Objective measures of oxygen consumption and carbon dioxide production by mammals are used to predict their energy expenditure. Since energy expenditure is not directly observable, it can be viewed as a latent construct with multiple physical indirect measures such as respiratory quotient, volumetric oxygen consumptio...

journal_title：Biometrics

authors： Tekwe CD,Zoh RS,Bazer FW,Wu G,Carroll RJ

更新日期：2018-03-01 00:00:00

abstract：:Matched case-control designs are commonly used in epidemiologic studies for increased efficiency. These designs have recently been introduced to the setting of modern imaging and genomic studies, which are characterized by high-dimensional covariates. However, appropriate statistical analyses that adjust for the match...

journal_title：Biometrics

authors： Qian J,Payabvash S,Kemmling A,Lev MH,Schwamm LH,Betensky RA

更新日期：2014-03-01 00:00:00

abstract：:Identifying factors associated with increased medical cost is important for many micro- and macro-institutions, including the national economy and public health, insurers and the insured. However, assembling comprehensive national databases that include both the cost and individual-level predictors can prove challengi...

journal_title：Biometrics

authors： Johnson BA,Long Q,Huang Y,Chansky K,Redman M

更新日期：2016-09-01 00:00:00

abstract：:Array-based CGH experiments are designed to detect genomic aberrations or regions of DNA copy-number variation that are associated with an outcome, typically a state of disease. Most of the existing statistical methods target on detecting DNA copy number variations in a single sample or array. We focus on the detectio...

journal_title：Biometrics

authors： Hu J,Zhang L,Wang HJ

更新日期：2016-09-01 00:00:00

abstract：:Logistic regression is a popular tool for risk analysis in medical and population health science. With continuous response data, it is common to create a dichotomous outcome for logistic regression analysis by specifying a threshold for positivity. Fitting a linear regression to the nondichotomized response variable a...

journal_title：Biometrics

authors： Schörgendorfer A,Branscum AJ,Hanson TE

更新日期：2013-06-01 00:00:00

abstract：:Identifying disease-associated changes in DNA methylation can help us gain a better understanding of disease etiology. Bisulfite sequencing allows the generation of high-throughput methylation profiles at single-base resolution of DNA. However, optimally modeling and analyzing these sparse and discrete sequencing data...

journal_title：Biometrics

authors： Zhao K,Oualkacha K,Lakhal-Chaieb L,Labbe A,Klein K,Ciampi A,Hudson M,Colmegna I,Pastinen T,Zhang T,Daley D,Greenwood CMT

更新日期：2020-05-21 00:00:00

abstract：:This paper presents an approach to handling missing covariates in the generalized estimating equation (GEE) model for binary outcomes when the probability of missingness depends on the observed outcomes and covariates. The proposed method is to replace the missing quantities in the estimating function with consistent ...

journal_title：Biometrics

authors： Xie F,Paik MC

更新日期：1997-12-01 00:00:00

abstract：:This paper focuses on the methodology developed for analyzing a multivariate interval-censored data set from an AIDS observational study. A purpose of the study was to determine the natural history of the opportunistic infection cytomeglovirus (CMV) in an HIV-infected individual. For this observational study, laborato...

journal_title：Biometrics

authors： Goggins WB,Finkelstein DM

更新日期：2000-09-01 00:00:00