Estimation of half-life periods in nonlinear data with fractional polynomials.

abstract：:This paper is based on a conference presentation in which several authors presented results from analyses of the same dataset concerning the evaluation of progression-free survival (PFS) as a surrogate endpoint for overall survival in advanced colorectal cancer clinical trials. In evaluating a potential surrogate endp...

journal_title：Statistical methods in medical research

authors： Hughes MD

更新日期：2008-10-01 00:00:00

abstract：:We review recent work on the application of pseudo-observations in survival and event history analysis. This includes regression models for parameters like the survival function in a single point, the restricted mean survival time and transition or state occupation probabilities in multi-state models, e.g. the competi...

journal_title：Statistical methods in medical research

authors： Andersen PK,Perme MP

更新日期：2010-02-01 00:00:00

abstract：:In this study, we discuss a decision theoretic or fully Bayesian approach to the sample size question in clinical trials with binary responses. Data are assumed to come from two binomial distributions. A Dirichlet distribution is assumed to describe prior knowledge of the two success probabilities p1 and p2. The param...

journal_title：Statistical methods in medical research

authors： Pezeshk H,Nematollahi N,Maroufy V,Marriott P,Gittins J

更新日期：2013-12-01 00:00:00

abstract：:In many experiments and especially in translational and preclinical research, sample sizes are (very) small. In addition, data designs are often high dimensional, i.e. more dependent than independent replications of the trial are observed. The present paper discusses the applicability of max t-test-type statistics (mu...

journal_title：Statistical methods in medical research

authors： Konietschke F,Schwab K,Pauly M

更新日期：2020-11-24 00:00:00

abstract：:Bayes or empirical Bayes methods to improve inferential accuracy for a population mean has been widely adopted in medical research. As the joint prior distribution of both the mean and variance parameters can be difficult to specify or estimate, most of these methods have relied on certain level of simplifications of ...

journal_title：Statistical methods in medical research

authors： Shen C

更新日期：2019-06-01 00:00:00

abstract：:Non-parametric linkage analysis examines similarities among affected relatives in alleles of one or more genetic markers (pieces of DNA at known locations on a chromosome). The objective is to evaluate departures from the null hypothesis that the markers are not near a disease gene. Under the null hypothesis, Mendel's...

journal_title：Statistical methods in medical research

authors： Shih MC,Whittemore AS

更新日期：2001-02-01 00:00:00

abstract：:One purpose of a longitudinal study is to gain a better understanding of how an outcome of interest changes among a given population over time. In what follows, a trajectory will be taken to mean the series of measurements of the outcome variable for an individual. Group-based trajectory modelling methods seek to iden...

journal_title：Statistical methods in medical research

authors： Davies CE,Glonek GF,Giles LC

更新日期：2017-08-01 00:00:00

abstract：:Semicompeting risks and interval censoring are frequent in medical studies, for instance when a disease may be diagnosed only at times of visit and disease onset is in competition with death. To evaluate the ability of markers to predict disease onset in this context, estimators of discrimination measures must account...

journal_title：Statistical methods in medical research

authors： Jacqmin-Gadda H,Blanche P,Chary E,Touraine C,Dartigues JF

更新日期：2016-12-01 00:00:00

abstract：:We propose a fully parametric model for the analysis of competing risks data where the types of failure may not be independent. We show how the dependence between the cause-specific survival times can be modelled with a copula function. Features include: identifiability of the problem; accessible understanding of the ...

journal_title：Statistical methods in medical research

authors： Escarela G,Carrière JF

更新日期：2003-08-01 00:00:00

abstract：:Medical research commonly relies on the combination of 2 x 2 tables of counted data for making inferences about treatment effects or about the causes of disease. This article reviews point estimation and interval estimation for a common odds ratio. Traditional methods for providing these estimates face special challen...

journal_title：Statistical methods in medical research

authors： Emerson JD

更新日期：1994-01-01 00:00:00

abstract：:Joint models for recurrent and terminal events have not been yet developed for clustered data. The goals of our study are to develop a statistical framework for modelling clustered recurrent and terminal events and to perform dynamic predictions of the terminal event in family studies. We propose a joint nested frailt...

journal_title：Statistical methods in medical research

authors： Choi YH,Jacqmin-Gadda H,Król A,Parfrey P,Briollais L,Rondeau V

更新日期：2020-05-01 00:00:00

abstract：:This paper reviews recent developments by the Washington/Brown groups for the study of anatomical shape in the emerging new discipline of computational anatomy. Parametric representations of anatomical variation for computational anatomy are reviewed, restricted to the assumption of small deformations. The generation ...

journal_title：Statistical methods in medical research

authors： Miller M,Banerjee A,Christensen G,Joshi S,Khaneja N,Grenander U,Matejic L

更新日期：1997-09-01 00:00:00

abstract：:In this paper, we describe a Bayesian hierarchical Poisson model for the prospective analysis of data for infectious diseases. The proposed model consists of two components. The first component describes the behavior of disease during nonepidemic periods and the second component represents the increase in disease coun...

journal_title：Statistical methods in medical research

authors： Corberán-Vallet A,Lawson AB

更新日期：2014-12-01 00:00:00

abstract：:In this paper, we develop a simple diagnostic test for the random-effects distribution in mixed models. The test is based on the gradient function, a graphical tool proposed by Verbeke and Molenberghs to check the impact of assumptions about the random-effects distribution in mixed models on inferences. Inference is c...

journal_title：Statistical methods in medical research

authors： Efendi A,Drikvandi R,Verbeke G,Molenberghs G

更新日期：2017-04-01 00:00:00

abstract：:Competing risks data often exist within a center in multi-center randomized clinical trials where the treatment effects or baseline risks may vary among centers. In this paper, we propose a subdistribution hazard regression model with multivariate frailty to investigate heterogeneity in treatment effects among centers...

journal_title：Statistical methods in medical research

authors： Ha ID,Christian NJ,Jeong JH,Park J,Lee Y

更新日期：2016-12-01 00:00:00

abstract：:Tracking a subject's risk factors or health status over time is an important objective in long-term epidemiological studies with repeated measurements. An important issue of time-trend tracking is to define appropriate statistical indices to quantitatively measure the tracking abilities of the targeted risk factors or...

journal_title：Statistical methods in medical research

authors： Wu CO,Tian X,Tian L,Reis JP,Zhao L,Allen NB,Bae S,Liu K

更新日期：2020-02-01 00:00:00

abstract：:We propose a semiparametric multi-state frailty model to analyze clustered event-history data subject to interval censoring. The proposed model is motivated by an attempt to study the life course of dental caries at the tooth level, taking into account the multiplicity of caries states and the intra-oral clustering of...

journal_title：Statistical methods in medical research

authors： Pak D,Li C,Todem D

更新日期：2019-09-01 00:00:00

abstract：:The accuracy of a diagnostic test, which is often quantified by a pair of measures such as sensitivity and specificity, is critical for medical decision making. Separate studies of an investigational diagnostic test can be combined through meta-analysis; however, such an analysis can be threatened by publication bias....

journal_title：Statistical methods in medical research

authors： Piao J,Liu Y,Chen Y,Ning J

更新日期：2019-10-01 00:00:00

abstract：:The classical and most commonly used approach to building prediction intervals is the parametric approach. However, its main drawback is that its validity and performance highly depend on the assumed functional link between the covariates and the response. This research investigates new methods that improve the perfor...

journal_title：Statistical methods in medical research

authors： Roy MH,Larocque D

更新日期：2020-01-01 00:00:00

abstract：:Multilevel models were originally developed to allow linear regression or ANOVA models to be applied to observations that are not mutually independent. This lack of independence commonly arises due to clustering of the units of observations into 'higher level units' such as patients in hospitals. In linear mixed model...

journal_title：Statistical methods in medical research

authors： Rabe-Hesketh S,Yang S,Pickles A

更新日期：2001-12-01 00:00:00

abstract：:Accelerated failure time model is a popular model to analyze censored time-to-event data. Analysis of this model without assuming any parametric distribution for the model error is challenging, and the model complexity is enhanced in the presence of large number of covariates. We developed a nonparametric Bayesian met...

journal_title：Statistical methods in medical research

authors： Zhang Z,Sinha S,Maiti T,Shipp E

更新日期：2018-04-01 00:00:00

abstract：:Cluster-level dynamic treatment regimens can be used to guide sequential treatment decision-making at the cluster level in order to improve outcomes at the individual or patient-level. In a cluster-level dynamic treatment regimen, the treatment is potentially adapted and re-adapted over time based on changes in the cl...

journal_title：Statistical methods in medical research

authors： NeCamp T,Kilbourne A,Almirall D

更新日期：2017-08-01 00:00:00

abstract：:Variable selection in semiparametric mixed models for longitudinal data remains a challenge, especially in the presence of multiple correlated outcomes. In this paper, we propose a model selection procedure that simultaneously selects fixed and random effects using a maximum penalized likelihood method with the adapti...

journal_title：Statistical methods in medical research

authors： Li Z,Liu H,Tu W

更新日期：2018-10-01 00:00:00

abstract：:We propose a flexible and computationally efficient penalized estimation method for a semi-parametric linear transformation model with current status data. To facilitate model fitting, the unknown monotone function is approximated by monotone B-splines, and a computationally efficient hybrid algorithm involving the Fi...

journal_title：Statistical methods in medical research

authors： Lu M,Liu Y,Li CS

更新日期：2020-01-01 00:00:00

abstract：:Increasing the clinical applicability of functional neuroimaging technology is an emerging objective, e.g. for diagnostic and treatment purposes. We propose a novel Bayesian spatial hierarchical framework for predicting follow-up neural activity based on an individual's baseline functional neuroimaging data. Our appro...

journal_title：Statistical methods in medical research

authors： Derado G,Bowman FD,Zhang L,Alzheimer's Disease Neuroimaging Initiative Investigators.

更新日期：2013-08-01 00:00:00

abstract：:It is a common practice to analyze longitudinal data frequently arisen in medical studies using various mixed-effects models in the literature. However, the following issues may standout in longitudinal data analysis: (i) In clinical practice, the profile of each subject's response from a longitudinal study may follow...

journal_title：Statistical methods in medical research

authors： Huang Y,Chen J,Yin P

更新日期：2017-02-01 00:00:00

abstract：:In multi-regional trials, the underlying overall and region-specific accrual rates often do not hold constant over time and different regions could have different start-up times, which combined with initial jump in accrual within each region often leads to a discontinuous overall accrual rate, and these issues associa...

journal_title：Statistical methods in medical research

authors： Deng Y,Zhang X,Long Q

更新日期：2017-04-01 00:00:00

abstract：:Trials run in either rare diseases, such as rare cancers, or rare sub-populations of common diseases are challenging in terms of identifying, recruiting and treating sufficient patients in a sensible period. Treatments for rare diseases are often designed for other disease areas and then later proposed as possible tre...

journal_title：Statistical methods in medical research

authors： Dutton P,Love SB,Billingham L,Hassan AB

更新日期：2018-05-01 00:00:00

abstract：:Identification of cancer patient subgroups using high throughput genomic data is of critical importance to clinicians and scientists because it can offer opportunities for more personalized treatment and overlapping treatments of cancers. In spite of tremendous efforts, this problem still remains challenging because o...

journal_title：Statistical methods in medical research

authors： Wei W,Sun Z,da Silveira WA,Yu Z,Lawson A,Hardiman G,Kelemen LE,Chung D

更新日期：2019-07-01 00:00:00

abstract：:There is debate whether clinical trials with suboptimal power are justified and whether results from large studies are more reliable than the (combined) results of smaller trials. We quantified the error rates for evaluations based on single conventionally powered trials (80% or 90% power) versus evaluations based on ...

journal_title：Statistical methods in medical research

authors： IntHout J,Ioannidis JP,Borm GF

更新日期：2016-04-01 00:00:00