Adaptive decision making in a lymphocyte infusion trial.

abstract：:Multipoint linkage analysis is being performed routinely in medical genetic studies to localize disease genes. This likelihood-based method is very computationally intensive. Exact computations are thus formidable for problems with large number of genetic markers and complex pedigrees. This paper proposes a Monte Carl...

journal_title：Biometrics

authors： Lin S

更新日期：1996-12-01 00:00:00

abstract：:In this article, we propose a Bayesian approach to dose-response assessment and the assessment of synergy between two combined agents. We consider the case of an in vitro ovarian cancer research study aimed at investigating the antiproliferative activities of four agents, alone and paired, in two human ovarian cancer ...

journal_title：Biometrics

authors： Hennessey VG,Rosner GL,Bast RC Jr,Chen MY

更新日期：2010-12-01 00:00:00

abstract：:Power and sample-size formulas for testing the homogeneity of relative risks using the score method are presented. The homogeneity score test (Gart, 1985, Biometrika 72, 673-677) is formally equivalent to the Pearson chi-square test, although they look different. Results of this paper may be useful in assessing the va...

journal_title：Biometrics

authors： Nam JM

更新日期：1999-03-01 00:00:00

abstract：:Interference occurs between individuals when the treatment (or exposure) of one individual affects the outcome of another individual. Previous work on causal inference methods in the presence of interference has focused on the setting where it is a priori assumed that there is "partial interference," in the sense that...

journal_title：Biometrics

authors： Loh WW,Hudgens MG,Clemens JD,Ali M,Emch ME

更新日期：2020-03-01 00:00:00

abstract：:The objective of this paper is to develop statistical methods for estimating current and future numbers of individuals in different stages of the natural history of the human immunodeficiency (AIDS) virus infection and to evaluate the impact of therapeutic advances on these numbers. The approach is to extend the metho...

journal_title：Biometrics

authors： Brookmeyer R,Liao JG

更新日期：1990-12-01 00:00:00

abstract：:A Bayesian multivariate adaptive regression spline fitting approach is used to model univariate and multivariate survival data with censoring. The possible models contain the proportional hazards model as a subclass and automatically detect departures from this. A reversible jump Markov chain Monte Carlo algorithm is ...

journal_title：Biometrics

authors： Mallick BK,Denison DG,Smith AF

更新日期：1999-12-01 00:00:00

abstract：:Statistical methods for the detection of genes influencing quantitative traits with the aid of genetic markers are well developed for normally distributed, fully observed phenotypes. Many experiments are concerned with failure-time phenotypes, which have skewed distributions and which are usually subject to censoring ...

journal_title：Biometrics

authors： Diao G,Lin DY

更新日期：2005-09-01 00:00:00

abstract：:The estimation of gene frequencies, linkage disequilibrium and disease associations for the human leukocyte antigen (HLA) system is considered. Comprehensive models for HLA data are introduced and contrasted with simpler approaches to the analysis of such data. ...

journal_title：Biometrics

authors： Farewell VT,Dahlberg S

更新日期：1984-06-01 00:00:00

abstract：:Covariate-specific receiver operating characteristic (ROC) curves are often used to evaluate the classification accuracy of a medical diagnostic test or a biomarker, when the accuracy of the test is associated with certain covariates. In many large-scale screening tests, the gold standard is subject to missingness due...

journal_title：Biometrics

authors： Liu D,Zhou XH

更新日期：2011-09-01 00:00:00

abstract：:Long-term follow-up is common in many medical investigations where the interest lies in predicting patients' risks for a future adverse outcome using repeatedly measured predictors over time. A key quantity is the likelihood of developing an adverse outcome among individuals who survived up to time s given their covar...

journal_title：Biometrics

authors： Maziarz M,Heagerty P,Cai T,Zheng Y

更新日期：2017-03-01 00:00:00

abstract：:This article proposes a two-stage simultaneous confidence procedure for the comparisons of k pairs of population means, without using multiplicity adjustment of more than two populations. The proposed procedure can be broadly applied to parametric or nonparametric models. It is robust and versatile because its derivat...

journal_title：Biometrics

authors： Chen JT

更新日期：2008-06-01 00:00:00

abstract：:This article develops a latent model and likelihood-based inference to detect temporal clustering of events. The model mimics typical processes generating the observed data. We apply model selection techniques to determine the number of clusters, and develop likelihood inference and a Monte Carlo expectation-maximizat...

journal_title：Biometrics

authors： Xie M,Sun Q,Naus J

更新日期：2009-12-01 00:00:00

abstract：:An adjusted rank correlation test is proposed as a technique for identifying publication bias in a meta-analysis, and its operating characteristics are evaluated via simulations. The test statistic is a direct statistical analogue of the popular "funnel-graph." The number of component studies in the meta-analysis, the...

journal_title：Biometrics

authors： Begg CB,Mazumdar M

更新日期：1994-12-01 00:00:00

abstract：:Multivariate current status data, consist of indicators of whether each of several events occur by the time of a single examination. Our interest focuses on inferences about the joint distribution of the event times. Conventional methods for analysis of multiple event-time data cannot be used because all of the event ...

journal_title：Biometrics

authors： Dunson DB,Dinse GE

更新日期：2002-03-01 00:00:00

abstract：:Moment methods for analyzing repeated binary responses have been proposed by Liang and Zeger (1986, Biometrika 73, 13-22), and extended by Prentice (1988, Biometrics 44, 1033-1048). In their generalized estimating equations (GEE), both Liang and Zeger (1986) and Prentice (1988) estimate the parameters associated with ...

journal_title：Biometrics

authors： Lipsitz SR,Fitzmaurice GM,Orav EJ,Laird NM

更新日期：1994-03-01 00:00:00

abstract：:We consider Bayesian methodology for comparing two or more unlabeled point sets. Application of the technique to a set of steroid molecules illustrates its potential utility involving the comparison of molecules in chemoinformatics and bioinformatics. We initially match a pair of molecules, where one molecule is regar...

journal_title：Biometrics

authors： Dryden IL,Hirst JD,Melville JL

更新日期：2007-03-01 00:00:00

abstract：:In clinical studies, longitudinal biomarkers are often used to monitor disease progression and failure time. Joint modeling of longitudinal and survival data has certain advantages and has emerged as an effective way to mutually enhance information. Typically, a parametric longitudinal model is assumed to facilitate t...

journal_title：Biometrics

authors： Ding J,Wang JL

更新日期：2008-06-01 00:00:00

abstract：:The receiver operating characteristic (ROC) curve is a prominent tool for characterizing the accuracy of a continuous diagnostic test. To account for factors that might influence the test accuracy, various ROC regression methods have been proposed. However, as in any regression analysis, when the assumed models do not...

journal_title：Biometrics

authors： Cai T,Zheng Y

更新日期：2007-03-01 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：:Recent advances in human genetics have led to a renewed interest in statistical methods for the detection of linkage from family data--for example, between marker loci and disease traits. Statistical analysis of linkage between two loci is carried out almost exclusively by means of the lod (log-odds) score test, equiv...

journal_title：Biometrics

authors： Shoukri MM,Lathrop GM

更新日期：1993-03-01 00:00:00

abstract：:Development of HIV resistance mutations is a major cause for failure of antiretroviral treatment. This article proposes a method for jointly modeling the processes of viral genetic changes and treatment failure. Because the viral genome is measured with uncertainty, a hidden Markov model is used to fit the viral genet...

journal_title：Biometrics

authors： Hu C,De Gruttola V

更新日期：2007-03-01 00:00:00

abstract：:The study of dynamical models of HIV infection, based on a system of nonlinear ordinary differential equations (ODE), has considerably improved the knowledge of its pathogenesis. While the first models used simplified ODE systems and analyzed each patient separately, recent works dealt with inference in non-simplified...

journal_title：Biometrics

authors： Guedj J,Thiébaut R,Commenges D

更新日期：2007-12-01 00:00:00

abstract：:The Wilcoxon rank sum test is widely used for two-group comparisons for nonnormal data. An assumption of this test is independence of sampling units both between and within groups. In ophthalmology, data are often collected on two eyes of an individual, which are highly correlated. In ophthalmological clinical trials,...

journal_title：Biometrics

authors： Rosner B,Glynn RJ,Lee ML

更新日期：2006-12-01 00:00:00

abstract：:In this article, we propose approximate sample size formulas for establishing equivalence or noninferiority of two treatments in match-pairs design. Using the ratio of two proportions as the equivalence measure, we derive sample size formulas based on a score statistic for two types of analyses: hypothesis testing and...

journal_title：Biometrics

authors： Tang ML,Tang NS,Chan IS,Chan BP

更新日期：2002-12-01 00:00:00

abstract：:We present a method for individual and integrative analysis of high dimension, low sample size data that capitalizes on the recurring theme in multivariate analysis of projecting higher dimensional data onto a few meaningful directions that are solutions to a generalized eigenvalue problem. We propose a general framew...

journal_title：Biometrics

authors： Safo SE,Ahn J,Jeon Y,Jung S

更新日期：2018-12-01 00:00:00

abstract：:A Bayesian adaptive design is proposed for dose-finding in phase I/II clinical trials to incorporate the bivariate outcomes, toxicity and efficacy, of a new treatment. Without specifying any parametric functional form for the drug dose-response curve, we jointly model the bivariate binary data to account for the corre...

journal_title：Biometrics

authors： Yin G,Li Y,Ji Y

更新日期：2006-09-01 00:00:00

abstract：:The use of summary rates of reporting health data is discussed. Directly and indirectly adjusted rates are compared under two models of no interaction. A method of analysis is described whereby a model is first fitted to data in order to investigate assumptions, and subsequently the smoothed rates based on the model a...

journal_title：Biometrics

authors： Freeman DH Jr,Holford TR

更新日期：1980-06-01 00:00:00

abstract：:Cluster analysis has proved to be an invaluable tool for the exploratory and unsupervised analysis of high-dimensional datasets. Among methods for clustering, hierarchical approaches have enjoyed substantial popularity in genomics and other fields for their ability to simultaneously uncover multiple layers of clusteri...

journal_title：Biometrics

authors： Kimes PK,Liu Y,Neil Hayes D,Marron JS

更新日期：2017-09-01 00:00:00

abstract：:Morrissey and Spiegelman (1999, Biometrics 55, 338 344) provided a comparative study of adjustment methods for exposure misclassification in case-control studies equipped with an internal validation sample. In addition to the maximum likelihood (ML) approach, they considered two intuitive procedures based on proposals...

journal_title：Biometrics

authors： Lyles RH

更新日期：2002-12-01 00:00:00

abstract：:Some covariate-adaptive randomization methods have been used in clinical trials for a long time, but little theoretical work has been done about testing hypotheses under covariate-adaptive randomization until Shao et al. (2010) who provided a theory with detailed discussion for responses under linear models. In this a...

journal_title：Biometrics

authors： Shao J,Yu X

更新日期：2013-12-01 00:00:00