Testing for central mixtures of compartment model parameters.

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：:We consider counting process methods for analysing time-to-event data with multiple or recurrent outcomes, using the models developed by Anderson and Gill, Wei, Lin and Weissfeld and Prentice, Williams and Peterson. We compare the methods, and show how to implement them using popular statistical software programs. By ...

journal_title：Statistics in medicine

authors： Therneau TM,Hamilton SA

更新日期：1997-09-30 00:00:00

abstract：:Summarizing the information of many studies using a meta-analysis becomes more and more important, also in the field of diagnostic studies. The special challenge in meta-analysis of diagnostic accuracy studies is that in general sensitivity and specificity are co-primary endpoints. Across the studies both endpoints ar...

journal_title：Statistics in medicine

authors： Zapf A,Hoyer A,Kramer K,Kuss O

更新日期：2015-12-20 00:00:00

abstract：:Proportional hazards (or Cox) regression is a popular method for modelling the effects of prognostic factors on survival. Use of cubic spline functions to model time-by-covariate interactions in Cox regression allows investigation of the shape of a possible covariate-time dependence without having to specify a specifi...

journal_title：Statistics in medicine

authors： Hess KR

更新日期：1994-05-30 00:00:00

abstract：:Risk prediction procedures can be quite useful for the patient's treatment selection, prevention strategy, or disease management in evidence-based medicine. Often, potentially important new predictors are available in addition to the conventional markers. The question is how to quantify the improvement from the new ma...

journal_title：Statistics in medicine

authors： Uno H,Tian L,Cai T,Kohane IS,Wei LJ

更新日期：2013-06-30 00:00:00

abstract：:Effective statistical help to biological and medical research demands thorough involvement of the statistician. The breadth of his activities can be illustrated by considering the questions he needs to discuss with his scientific colleagues in the course of planning a comparative experiment. The paper presents and com...

journal_title：Statistics in medicine

authors： Finney DJ

更新日期：1982-01-01 00:00:00

abstract：:The percentile-finding experimental design known variously as 'forced-choice fixed-staircase', 'geometric up-and-down' or 'k-in-a-row' (KR) was introduced by Wetherill four decades ago. To date, KR has been by far the most widely used up-and-down (U&D) design for estimating non-median percentiles; it is implemented mo...

journal_title：Statistics in medicine

authors： Oron AP,Hoff PD

更新日期：2009-06-15 00:00:00

abstract：:Evaluating treatment effects within different subsets of patients is a common practice in the analysis of individual randomized clinical trials. Such analyses are limited, however, by the number of patients available. Overviews, by providing evidence based on large numbers of patients, can be useful for overcoming the...

journal_title：Statistics in medicine

authors： Gelber RD,Goldhirsch A

更新日期：1987-04-01 00:00:00

abstract：:Binary matched-pairs data occur commonly in longitudinal studies, such as in cross-over experiments. Many analyses for comparing the matched probabilities of a particular outcome do not utilize pairs having the same outcome for each observation. An example is McNemar's test. Some methodologists find this to be counter...

journal_title：Statistics in medicine

authors： Agresti A,Min Y

更新日期：2004-01-15 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：:This paper discusses regression analysis of multivariate current status failure time data (The Statistical Analysis of Interval-censoring Failure Time Data. Springer: New York, 2006), which occur quite often in, for example, tumorigenicity experiments and epidemiologic investigations of the natural history of a diseas...

journal_title：Statistics in medicine

authors： Chen MH,Tong X,Sun J

更新日期：2009-11-30 00:00:00

abstract：:This paper presents combinatorial (exact) methods that are useful in the analysis of disease cluster data obtained from small environments, such as buildings and neighbourhoods. Maxwell-Boltzmann and Fermi-Dirac occupancy models are compared in terms of appropriateness of representation of disease incidence patterns (...

journal_title：Statistics in medicine

authors： Grimson RC

更新日期：1993-10-01 00:00:00

abstract：:Multilevel and longitudinal studies are frequently subject to missing data. For example, biomarker studies for oral cancer may involve multiple assays for each participant. Assays may fail, resulting in missing data values that can be assumed to be missing completely at random. Catellier and Muller proposed a data ana...

journal_title：Statistics in medicine

authors： Ringham BM,Kreidler SM,Muller KE,Glueck DH

更新日期：2016-07-30 00:00:00

abstract：:Quality of life (QOL) assessment is a key component of many clinical studies and frequently requires the use of single global summary measures that capture the overall balance of findings from a potentially wide-ranging assessment of QOL issues. We propose and evaluate an irregular multilevel latent variable model sui...

journal_title：Statistics in medicine

authors： Kifley A,Heller GZ,Beath KJ,Bulger D,Ma J,Gebski V

更新日期：2012-05-20 00:00:00

abstract：:We consider the estimation of parameters in a particular segmented generalized linear model with additive measurement error in predictors, with a focus on linear and logistic regression. In epidemiologic studies segmented regression models often occur as threshold models, where it is assumed that the exposure has no i...

journal_title：Statistics in medicine

authors： Küchenhoff H,Carroll RJ

更新日期：1997-01-15 00:00:00

abstract：:Meta-analyses pooling continuous outcomes can use mean differences (MD), standardized MD (MD in pooled standard deviation units, SMD), or ratio of arithmetic means (RoM). Recently, ratio of geometric means using ad hoc (RoGM (ad hoc) ) or Taylor series (RoGM (Taylor) ) methods for estimating variances have been propos...

journal_title：Statistics in medicine

authors： Friedrich JO,Adhikari NK,Beyene J

更新日期：2012-07-30 00:00:00

abstract：:In this paper, we develop methods to combine multiple biomarker trajectories into a composite diagnostic marker using functional data analysis (FDA) to achieve better diagnostic accuracy in monitoring disease recurrence in the setting of a prospective cohort study. In such studies, the disease status is usually verifi...

journal_title：Statistics in medicine

authors： Li H,Gatsonis C

更新日期：2019-05-20 00:00:00

abstract：:We examine the use of randomization-based inference for analyzing multiarmed randomized clinical trials, including the application of conditional randomization tests to multiple comparisons. The view is taken that the linkage of the statistical test to the experimental design (randomization procedure) should be recogn...

journal_title：Statistics in medicine

authors： Wang Y,Rosenberger WF,Uschner D

更新日期：2020-02-20 00:00:00

abstract：:In studies with survival or time-to-event outcomes, a competing risk is an event whose occurrence precludes the occurrence of the primary event of interest. Specialized statistical methods must be used to analyze survival data in the presence of competing risks. We conducted a review of randomized controlled trials wi...

journal_title：Statistics in medicine

authors： Austin PC,Fine JP

更新日期：2017-04-15 00:00:00

abstract：:Vaccination in populations can have several kinds of effects. Establishing that vaccination produces population-level effects beyond the direct effects in the vaccinated individuals can have important consequences for public health policy. Formal methods have been developed for study designs and analysis that can esti...

journal_title：Statistics in medicine

authors： Halloran ME,Hudgens MG

更新日期：2018-01-30 00:00:00

abstract：:Relative potency is a measure that has been used for many years to summarize the comparison of dose-response curves in parallel line bioassays. When response curves for two preparations are not parallel the traditional definition of relative potency no longer applies. We review the concept of relative potency and show...

journal_title：Statistics in medicine

authors： Kaiser MS,Siev D

更新日期：1997-05-30 00:00:00

abstract：:The estimation of attributable risk in the presence of confounding and effect modification is studied in this paper. Different adjustment methods for the attributable risk are reviewed. The results of a stimulation study comparing these methods under the unrestricted multinomial sampling model are reported. From the s...

journal_title：Statistics in medicine

authors： Gefeller O

更新日期：1992-12-01 00:00:00

abstract：:There is an increasing interest in the use of propensity score methods to estimate causal effects in observational studies. However, recent systematic reviews have demonstrated that propensity score methods are inconsistently used and frequently poorly applied in the medical literature. In this study, we compared the ...

journal_title：Statistics in medicine

authors： Austin PC,Mamdani MM

更新日期：2006-06-30 00:00:00

abstract：:Day and Walter derived methods of joint maximum likelihood estimation for the sojourn time distribution and the false negative rate for a screening programme. Their methods are not directly applicable to a programme which uses alternate screening by two modalities whose sojourn times and false negative rates will diff...

journal_title：Statistics in medicine

authors： Alexander FE

更新日期：1989-06-01 00:00:00

abstract：:The goal of screening programmes for cancer is early detection and treatment with a consequent reduction in mortality from the disease. Screening programmes need to assess the true benefit of screening, that is, the length of time of extension of survival beyond the time of advancement of diagnosis (lead-time). This p...

journal_title：Statistics in medicine

authors： Xu JL,Prorok PC

更新日期：1995-12-30 00:00:00

abstract：:The general linear mixed model provides a useful approach for analysing a wide variety of data structures which practising statisticians often encounter. Two such data structures which can be problematic to analyse are unbalanced repeated measures data and longitudinal data. Owing to recent advances in methods and sof...

journal_title：Statistics in medicine

authors： Cnaan A,Laird NM,Slasor P

更新日期：1997-10-30 00:00:00

abstract：:Longitudinal studies are often concerned with estimating the recurrence rate of a non-fatal event. In many cases, only the total number of events occurring during successive time intervals is known. We compared a mixed Poisson-gamma regression method proposed by Thall and a quasi-likelihood method proposed by Zeger an...

journal_title：Statistics in medicine

authors： Stukel TA

更新日期：1993-07-30 00:00:00

abstract：:Correlation analysis is widely used in biomedical and psychosocial research for assessing rater reliability, precision of diagnosis and accuracy of proxy outcomes. The popularity of longitudinal study designs has propelled the proliferation in recent years of new methods for longitudinal and other multi-level clustere...

journal_title：Statistics in medicine

authors： Tu XM,Feng C,Kowalski J,Tang W,Wang H,Wan C,Ma Y

更新日期：2007-09-30 00:00:00

abstract：:This paper investigates the design and analysis of dose-finding trials with two agents. The set of doses for each agent is fixed in advance. The goal of the trial is to find the set of dose combinations with probability of toxicity closest to a pre-specified value. For each of the two agents we assume that the probabi...

journal_title：Statistics in medicine

authors： Ivanova A,Wang K

更新日期：2004-06-30 00:00:00

abstract：:We review two recent trends: the emergence of evidence-based medicine and the growing use of Bayesian statistics in medical applications. Evidence-based medicine requires an integrated assessment of the available evidence, and associated uncertainty, but there is also an emphasis on decision-making, for individual pat...

journal_title：Statistics in medicine

authors： Ashby D,Smith AF

更新日期：2000-12-15 00:00:00