Analysis of ordered composite endpoints.

abstract：:We develop parametric maximum likelihood methods to adjust for treatment changes during follow-up in order to assess the causal effect of treatment in clinical trials with time-to-event outcomes. The accelerated failure time model of Robins and Tsiatis relates each observed event time to the underlying event time that...

journal_title：Statistics in medicine

authors： Walker AS,White IR,Babiker AG

更新日期：2004-02-28 00:00:00

abstract：BACKGROUND:Multiple imputation is becoming increasingly popular for handling missing data, with Markov chain Monte Carlo assuming multivariate normality (MVN) a commonly used approach. Imputing categorical variables (which are clearly non-normal) using MVN imputation is challenging, and several approaches have been sug...

journal_title：Statistics in medicine

authors： Lee KJ,Galati JC,Simpson JA,Carlin JB

更新日期：2012-12-30 00:00:00

abstract：:Public health interventions are often designed to target communities defined either geographically (e.g. cities, counties) or socially (e.g. schools or workplaces). The group randomized trial (GRT) is regarded as the gold standard for evaluating these interventions. However, community leaders may object to randomizati...

journal_title：Statistics in medicine

authors： Pennell ML,Hade EM,Murray DM,Rhoda DA

更新日期：2011-07-10 00:00:00

abstract：:We develop a simulation-based procedure for determining the required sample size in binomial regression risk assessment studies when response data are subject to misclassification. A Bayesian average power criterion is used to determine a sample size that provides high probability, averaged over the distribution of po...

journal_title：Statistics in medicine

authors： Cheng D,Stamey JD,Branscum AJ

更新日期：2009-02-28 00:00:00

abstract：:Some clinical trials aim to demonstrate therapeutic equivalence on multiple primary endpoints. For example, therapeutic equivalence studies of agents for the treatment of osteoarthritis use several primary endpoints including investigator's global assessment of disease activity, patient's global assessment of response...

journal_title：Statistics in medicine

authors： Quan H,Bolognese J,Yuan W

更新日期：2001-11-15 00:00:00

abstract：:Laboratory determinations on children aged 6 to 10 years obtained over a 5-year period are analysed by a method described in detail for differentiating between children from exposed and control areas of Seveso, Italy. In the analysis, stratification is employed to distinguish the separate days of laboratory measuremen...

journal_title：Statistics in medicine

authors： Mantel N,Mocarelli P,Marocchi A,Brambilla P,Baretta R

更新日期：1983-04-01 00:00:00

abstract：:This paper gives a standard error for Cohen's Kappa, conditional on the margins of the observed r x r table. An explicit formula is given for the 2 x 2 table, and a procedure for the more general situation. A parsimonious log-linear model is suggested for the general case and an approximate confidence interval for kap...

journal_title：Statistics in medicine

authors： Garner JB

更新日期：1991-05-01 00:00:00

abstract：:A trial of Duchenne muscular dystrophy involved tracking boys of all ages through a one-year baseline period, followed by a one-year trial of leucine versus placebo treatment. In this paper we develop a model for a total-muscle-strength score that uses the data of the extended baseline period in the evaluation of the ...

journal_title：Statistics in medicine

authors： Madsen KS,Miller JP,Province MA

更新日期：1986-05-01 00:00:00

abstract：:For genome-wide association studies, we propose a new method for identifying significant biological pathways. In this approach, we aggregate data across single-nucleotide polymorphisms to obtain summary measures at the gene level. We then use a hierarchical Bayesian model, which takes the gene-level summary measures a...

journal_title：Statistics in medicine

authors： Shahbaba B,Shachaf CM,Yu Z

更新日期：2012-05-10 00:00:00

abstract：:I discuss alternatives to the one compartment model, delta Yt = alpha + beta exp(- gamma t). Instead of comparing the one and two compartment models, I derive statistics for testing mixtures of the parameters (beta, gamma) in the one compartment model. I apply the proposed methods to the problem of hydrogen clearance ...

journal_title：Statistics in medicine

authors： Zelterman D

更新日期：1989-08-01 00:00:00

abstract：:Diseases can be interconnected. In the recent years, there has been a surge of multidisease studies. Among them, HDN (human disease network) analysis takes a system perspective, examines the interconnections among diseases along with their individual properties, and has demonstrated great potential. Most of the existi...

journal_title：Statistics in medicine

authors： Ma C,Li Y,Shia B,Ma S

更新日期：2020-04-30 00:00:00

abstract：:Assessing the calibration of methods for estimating the probability of the occurrence of a binary outcome is an important aspect of validating the performance of risk-prediction algorithms. Calibration commonly refers to the agreement between predicted and observed probabilities of the outcome. Graphical methods are a...

journal_title：Statistics in medicine

authors： Austin PC,Steyerberg EW

更新日期：2019-09-20 00:00:00

abstract：:Lower urinary tract symptoms can indicate the presence of urinary tract infection (UTI), a condition that if it becomes chronic requires expensive and time consuming care as well as leading to reduced quality of life. Detecting the presence and gravity of an infection from the earliest symptoms is then highly valuable...

journal_title：Statistics in medicine

authors： Barcella W,Iorio MD,Baio G,Malone-Lee J

更新日期：2016-04-15 00:00:00

abstract：:We consider the design of both cohort and case-control studies in which an initial ('stage 1') sample of complete data on an error-free disease indicator (D), a correct ('gold standard') dichotomous exposure measurement (X) and an error-prone exposure measurement (Z) are available. We calculate the amount of additiona...

journal_title：Statistics in medicine

authors： Dahm PF,Gail MH,Rosenberg PS,Pee D

更新日期：1995-12-15 00:00:00

abstract：:Bivariate survival data arise, for example, in twin studies and studies of both eyes or ears of the same individual. Often it is of interest to regress the survival times on a set of predictors. In this paper we extend Wei and Tanner's multiple imputation approach for linear regression with univariate censored data to...

journal_title：Statistics in medicine

authors： Pan W,Kooperberg C

更新日期：1999-11-30 00:00:00

abstract：:The incremental life expectancy, defined as the difference in mean survival times between two treatment groups, is a crucial quantity of interest in cost-effectiveness analyses. Usually, this quantity is very difficult to estimate from censored survival data with a limited follow-up period. The paper develops estimati...

journal_title：Statistics in medicine

authors： Titman AC

更新日期：2016-09-10 00:00:00

abstract：:Although there are many models which are used to calculate the health benefits (and thus the cost-effectiveness) of vaccination programmes, they can be divided into two groups: those which assume a constant force of infection, that is a constant per-susceptible rate of infection; and those which assume that the force ...

journal_title：Statistics in medicine

authors： Edmunds WJ,Medley GF,Nokes DJ

更新日期：1999-12-15 00:00:00

abstract：:We describe rank-based approaches to assess principal stratification treatment effects in studies where the outcome of interest is only well-defined in a subgroup selected after randomization. Our methods are sensitivity analyses, in that estimands are identified by fixing a parameter and then we investigate the sensi...

journal_title：Statistics in medicine

authors： Lu X,Mehrotra DV,Shepherd BE

更新日期：2013-11-20 00:00:00

abstract：:Genome-wide association studies are characterized by a huge number of statistical tests performed to discover new disease-related genetic variants [in the form of single-nucleotide polymorphisms (SNPs)] in human DNA. Many SNPs have been identified for cross-sectionally measured phenotypes. However, there is a growing ...

journal_title：Statistics in medicine

authors： Sikorska K,Rivadeneira F,Groenen PJ,Hofman A,Uitterlinden AG,Eilers PH,Lesaffre E

更新日期：2013-01-15 00:00:00

abstract：:Cox proportional hazard regression model is a popular tool to analyze the relationship between a censored lifetime variable with other relevant factors. The semiparametric Cox model is widely used to study different types of data arising from applied disciplines such as medical science, biology, and reliability studie...

journal_title：Statistics in medicine

authors： Ghosh A,Basu A

更新日期：2019-11-30 00:00:00

abstract：:We consider the analysis of serial biomarkers to screen and monitor individuals in a given population for onset of a specific disease of interest. The biomarker readings are subject to error. We survey some of the existing literature and concentrate on two recently proposed models. The first is a fully Bayesian hierar...

journal_title：Statistics in medicine

authors： Slate EH,Turnbull BW

更新日期：2000-02-29 00:00:00

abstract：:The World Health Organization and collaborating institutions in four developing countries have conducted a multi-centre randomized controlled trial, in which clinics were allocated at random to two antenatal care (ANC) models. These were the standard 'Western' ANC model and a 'new' ANC model consisting of tests, clini...

journal_title：Statistics in medicine

authors： Piaggio G,Carroli G,Villar J,Pinol A,Bakketeig L,Lumbiganon P,Bergsjø P,Al-Mazrou Y,Ba'aqeel H,Belizán JM,Farnot U,Berendes H,WHO Antenatal Care Trial Research Group.

更新日期：2001-02-15 00:00:00

abstract：:The receiver operating characteristic (ROC) curve can be utilized to evaluate the performance of diagnostic tests. The area under the ROC curve (AUC) is a widely used summary index for comparing multiple ROC curves. Both parametric and nonparametric methods have been developed to estimate and compare the AUCs. However...

journal_title：Statistics in medicine

authors： Yao W,Li Z,Graubard BI

更新日期：2015-04-15 00:00:00

abstract：:Genetic markers can be used as instrumental variables, in an analogous way to randomization in a clinical trial, to estimate the causal relationship between a phenotype and an outcome variable. Our purpose is to extend the existing methods for such Mendelian randomization studies to the context of multiple genetic mar...

journal_title：Statistics in medicine

authors： Burgess S,Thompson SG,CRP CHD Genetics Collaboration.,Burgess S,Thompson SG,Andrews G,Samani NJ,Hall A,Whincup P,Morris R,Lawlor DA,Davey Smith G,Timpson N,Ebrahim S,Ben-Shlomo Y,Davey Smith G,Timpson N,Brown M,Ricket

更新日期：2010-05-30 00:00:00

abstract：:The need for resource-intensive laboratory assays to assess exposures in many epidemiologic studies provides ample motivation to consider study designs that incorporate pooled samples. In this paper, we consider the case in which specimens are combined for the purpose of determining the presence or absence of a pool-w...

journal_title：Statistics in medicine

authors： Lyles RH,Tang L,Lin J,Zhang Z,Mukherjee B

更新日期：2012-09-28 00:00:00

abstract：:In the presence of confounding, the consistency assumption required for identification of causal effects may be violated due to misclassification of the outcome variable. We introduce an inverse probability weighted approach to rebalance covariates across treatment groups while mitigating the influence of differential...

journal_title：Statistics in medicine

authors： Gravel CA,Platt RW

更新日期：2018-02-10 00:00:00

abstract：:Pearson's chi-squared, the likelihood-ratio, and Fisher-Freeman-Halton's test statistics are often used to test the association of unordered r x c tables. Asymptotical, exact conditional, or exact conditional with mid-p adjustment methods are commonly used to compute the p-value. We have compared test power and signif...

journal_title：Statistics in medicine

authors： Lydersen S,Pradhan V,Senchaudhuri P,Laake P

更新日期：2007-10-15 00:00:00

abstract：:Analysis of panel data is often challenged by the presence of heterogeneity and state misclassification. In this paper, we propose a hidden mover-stayer model to facilitate heterogeneity for a population that consists of two subpopulations each of movers or of stayers and to simultaneously account for state misclassif...

journal_title：Statistics in medicine

authors： Yi GY,He W,He F

更新日期：2017-09-10 00:00:00

abstract：:We present some practical extensions and applications of a strategy proposed by Thall, Simon and Estey for designing and monitoring single-arm clinical trials with multiple outcomes. We show by application how the strategy may be applied to construct designs for phase IIA activity trials and phase II equivalence trial...

journal_title：Statistics in medicine

authors： Thall PF,Sung HG

更新日期：1998-07-30 00:00:00

abstract：:Biomedical studies often measure variables with error. Examples in the literature include investigation of the association between the change in some outcome variable (blood pressure, cholesterol level etc.) and a set of explanatory variables (age, smoking status etc.). Typically, one fits linear regression models to ...

journal_title：Statistics in medicine

authors： Yanez ND 3rd,Kronmal RA,Shemanski LR

更新日期：1998-11-30 00:00:00