Graphical model checking with correlated response data.

abstract：:Predicting an individual's risk of experiencing a future clinical outcome is a statistical task with important consequences for both practicing clinicians and public health experts. Modern observational databases such as electronic health records provide an alternative to the longitudinal cohort studies traditionally ...

journal_title：Statistics in medicine

authors： Wolfson J,Bandyopadhyay S,Elidrisi M,Vazquez-Benitez G,Vock DM,Musgrove D,Adomavicius G,Johnson PE,O'Connor PJ

更新日期：2015-09-20 00:00:00

abstract：:It is often assumed that randomisation will prevent bias in estimation of treatment effects from clinical trials, but this is not true of the semiparametric Proportional Hazards model for survival data when there is underlying risk heterogeneity. Here, a new formula is proposed for estimation of this bias, improving o...

journal_title：Statistics in medicine

authors： McNamee R

更新日期：2017-09-20 00:00:00

abstract：:In conventional survival analysis there is an underlying assumption that all study subjects are susceptible to the event. In general, this assumption does not adequately hold when investigating the time to an event other than death. Owing to genetic and/or environmental etiology, study subjects may not be susceptible ...

journal_title：Statistics in medicine

authors： Chen CH,Tsay YC,Wu YC,Horng CF

更新日期：2013-10-30 00:00:00

abstract：:In many community-based studies on the incidence of dementia, a target population is screened and a subsample is clinically evaluated at baseline and follow-up. Incidence rates are affected by missed cases at both exams and this complicates the estimation of these rates. Recent work proposes a regression-based techniq...

journal_title：Statistics in medicine

authors： Izmirlian G,Brock D,White L

更新日期：2000-06-15 00:00:00

abstract：:This paper investigates the Bayesian procedures for comparing proportions. These procedures are especially suitable for accepting (or rejecting) the equivalence of two population proportions. Furthermore the Bayesian predictive probabilities provide a natural and flexible tool in monitoring trials, especially for choo...

journal_title：Statistics in medicine

authors： Lecoutre B,Derzko G,Grouin JM

更新日期：1995-05-15 00:00:00

abstract：:Adaptive designs have been proposed for clinical trials in which the nuisance parameters or alternative of interest are unknown or likely to be misspecified before the trial. Although most previous works on adaptive designs and mid-course sample size re-estimation have focused on two-stage or group-sequential designs ...

journal_title：Statistics in medicine

authors： Bartroff J,Lai TL

更新日期：2008-05-10 00:00:00

abstract：:The validity and practical utility of observational medical research depends critically on good study design, excellent data quality, appropriate statistical methods and accurate interpretation of results. Statistical methodology has seen substantial development in recent times. Unfortunately, many of these methodolog...

journal_title：Statistics in medicine

authors： Sauerbrei W,Abrahamowicz M,Altman DG,le Cessie S,Carpenter J,STRATOS initiative.

更新日期：2014-12-30 00:00:00

abstract：:Flexible survival models are in need when modelling data from long term follow-up studies. In many cases, the assumption of proportionality imposed by a Cox model will not be valid. Instead, a model that can identify time varying effects of fixed covariates can be used. Although there are several approaches that deal ...

journal_title：Statistics in medicine

authors： Perperoglou A

更新日期：2016-12-10 00:00:00

abstract：:In modern observational studies using electronic health records or other routinely collected data, both the outcome and covariates of interest can be error-prone and their errors often correlated. A cost-effective solution is the two-phase design, under which the error-prone outcome and covariates are observed for all...

journal_title：Statistics in medicine

authors： Tao R,Lotspeich SC,Amorim G,Shaw PA,Shepherd BE

更新日期：2021-02-10 00:00:00

abstract：:In a longitudinal study of workers in seven Norwegian aluminium plants, the time to development of asthmatic symptoms could only be determined to lie in the interval between two consecutive health examinations. In a previous paper we analysed the data by survival techniques for interval censored data. In the present p...

journal_title：Statistics in medicine

authors： Samuelsen SO,Kongerud J

更新日期：1994-09-15 00:00:00

abstract：:A method has been developed for simultaneously comparing the usefulness of many treatments of established value for symptomatic medical conditions. Medical assessment of outcome is not employed. Instead patients are required to assess treatments prescribed during the course of ordinary general practice rather than und...

journal_title：Statistics in medicine

authors： Charlton JR,D'Souza MF,Tooley M,Silver R

更新日期：1985-01-01 00:00:00

abstract：:Conditional power based on summary statistic by comparing outcomes (such as the sample mean) directly between 2 groups is a convenient tool for decision making in randomized controlled trial studies. In this paper, we extend the traditional summary statistic-based conditional power with a general model-based assessmen...

journal_title：Statistics in medicine

authors： Zou B,Cai J,Koch GG,Zhou H,Zou F

更新日期：2017-12-30 00:00:00

abstract：:This paper presents a simple method for estimation of population vaccination effectiveness, which is the fraction of disease cases prevented by a vaccination programme. The method is based on the susceptible-infectious-recovered (SIR) model for the spread of an epidemic in a heterogeneous population under non-homogene...

journal_title：Statistics in medicine

authors： Haber M

更新日期：1997-03-30 00:00:00

abstract：:Outcome-dependent sampling (ODS) scheme is a cost-effective sampling scheme where one observes the exposure with a probability that depends on the outcome. The well-known such design is the case-control design for binary response, the case-cohort design for the failure time data, and the general ODS design for a conti...

journal_title：Statistics in medicine

authors： Lu TS,Longnecker MP,Zhou H

更新日期：2017-03-15 00:00:00

abstract：:In failure time studies involving a chronic disease such as cancer, several competing causes of mortality may be operating. Commonly, the conventional statistical technique of Kaplan-Meier, which is only meaningfully interpreted by assuming independence of failure types and the censoring mechanism, is employed in clin...

journal_title：Statistics in medicine

authors： Tai BC,Machin D,White I,Gebski V,EOI (The European Osteosarcoma Intergroup).

更新日期：2001-03-15 00:00:00

abstract：:We studied the problem of testing a hypothesized distribution in survival regression models when the data is right censored and survival times are influenced by covariates. A modified chi-squared type test, known as Nikulin-Rao-Robson statistic, is applied for the comparison of accelerated failure time models. This st...

journal_title：Statistics in medicine

authors： Tahir MR,Tran QX,Nikulin MS

更新日期：2017-05-30 00:00:00

abstract：:Longitudinal biomarker data are often collected in studies, providing important information regarding the probability of an outcome of interest occurring at a future time. With many new and evolving technologies for biomarker discovery, the number of biomarker measurements available for analysis of disease progression...

journal_title：Statistics in medicine

authors： Zhao L,Murray S,Mariani LH,Ju W

更新日期：2020-11-20 00:00:00

abstract：:Assay sensitivity has been proposed as a criterion for including psychiatric clinical outcome studies in meta-analyses. The authors assess the performance of assay sensitivity as a method for determining study appropriateness for meta-analysis by calculating expected standard drug vs placebo effect sizes for various c...

journal_title：Statistics in medicine

authors： Gelfand LA,Strunk DR,Tu XM,Noble RE,Derubeis RJ

更新日期：2006-03-30 00:00:00

abstract：:The identification of new adverse drug reactions is often tricky. For a given case, the relationship between drug exposure and symptom occurrence is usually questionable. It could be investigated statistically from a series of drug-event association cases with an independence test between the two variables. Analysing ...

journal_title：Statistics in medicine

authors： Tubert P,Begaud B

更新日期：1991-06-01 00:00:00

abstract：:Comparative effectiveness research represents the kind of research that arguably more directly affects clinical practice and policy. It includes observational studies, clinical trials, and systematic syntheses of existing literature. In this commentary, I argue for the ongoing and critical role of randomization in com...

journal_title：Statistics in medicine

authors： Lauer MS

更新日期：2012-11-10 00:00:00

abstract：:Cancer immunotherapy trials have two special features: a delayed treatment effect and a cure rate. Both features violate the proportional hazard model assumption and ignoring either one of the two features in an immunotherapy trial design will result in substantial loss of statistical power. To properly design immunot...

journal_title：Statistics in medicine

authors： Wei J,Wu J

更新日期：2020-03-15 00:00:00

abstract：:Virtually all clinical trials collect multiple endpoints that are usually correlated. Many methods have been proposed to control the family-wise type I error rate (FWER), but these methods often disregard the correlation among the endpoints, such as the commonly used Bonferroni correction, Holm procedure, Wiens' Bonfe...

journal_title：Statistics in medicine

authors： Xie C

更新日期：2012-02-20 00:00:00

abstract：:In observational studies, many continuous or categorical covariates may be related to an outcome. Various spline-based procedures or the multivariable fractional polynomial (MFP) procedure can be used to identify important variables and functional forms for continuous covariates. This is the main aim of an explanatory...

journal_title：Statistics in medicine

authors： Binder H,Sauerbrei W,Royston P

更新日期：2013-06-15 00:00:00

abstract：:To compare the survival functions based on right-truncated data, Lagakos et al. proposed a weighted logrank test based on a reverse time scale. This is in contrast to Bilker and Wang, who suggested a semi-parametric version of the Mann-Whitney test by assuming that the distribution of truncation times is known or can ...

journal_title：Statistics in medicine

authors： Chi Y,Tsai WY,Chiang CL

更新日期：2007-02-20 00:00:00

abstract：:Health questionnaires are often built up from sets of questions that are totaled to obtain a sum score. An important consideration in designing questionnaires is to minimize respondent burden. An increasingly popular method for efficient measurement is computerized adaptive testing; unfortunately, many health question...

journal_title：Statistics in medicine

authors： Smits N,Finkelman MD

更新日期：2014-02-10 00:00:00

abstract：:We propose an innovative and practically relevant clustering method to find common task-related brain regions among different subjects who respond to the same set of stimuli. Using functional magnetic resonance imaging (fMRI) time series data, we first cluster the voxels within each subject on a voxel by voxel basis. ...

journal_title：Statistics in medicine

authors： Ye J,Li Y,Lazar NA,Schaeffer DJ,McDowell JE

更新日期：2016-07-10 00:00:00

abstract：:Clinical trials studying treatments for rare diseases are challenging to design and conduct due to the limited number of patients eligible for the trial. One design used to address this challenge is the small n, sequential, multiple assignment, randomized trial (snSMART). We propose a new snSMART design that investiga...

journal_title：Statistics in medicine

authors： Fang F,Hochstedler KA,Tamura RN,Braun TM,Kidwell KM

更新日期：2021-02-20 00:00:00

abstract：:We propose a new weighted hurdle regression method for modeling count data, with particular interest in modeling cardiovascular events in patients on dialysis. Cardiovascular disease remains one of the leading causes of hospitalization and death in this population. Our aim is to jointly model the relationship/associat...

journal_title：Statistics in medicine

authors： Sentürk D,Dalrymple LS,Mu Y,Nguyen DV

更新日期：2014-11-10 00:00:00

abstract：:The problem of evaluating an averaged functional magnetic resonance imaging (fMRI) response for repeated block design experiments was considered within a semiparametric regression model with autocorrelated residuals. We applied functional data analysis (FDA) techniques that use a least-squares fitting of B-spline expa...

journal_title：Statistics in medicine

authors： Vakorin VA,Borowsky R,Sarty GE

更新日期：2007-09-20 00:00:00

abstract：:Three-arm trials including the experimental treatment, an active reference treatment and a placebo are recommended in the guidelines of the ICH and EMEA/CPMP as a useful approach to the assessment of assay sensitivity. Generally, the acceptable non-inferiority margin Δ has been defined as the maximum clinically irrele...

journal_title：Statistics in medicine

authors： Hida E,Tango T

更新日期：2011-02-10 00:00:00