The questioning statistician.

abstract：:Methods for addressing multiplicity in clinical trials have attracted much attention during the past 20 years. They include the investigation of new classes of multiple test procedures, such as fixed sequence, fallback and gatekeeping procedures. More recently, sequentially rejective graphical test procedures have bee...

journal_title：Statistics in medicine

authors： Maurer W,Bretz F

更新日期：2013-05-10 00:00:00

abstract：:There is growing interest in how best to adapt and readapt treatments to individuals to maximize clinical benefit. In response, adaptive treatment strategies (ATS), which operationalize adaptive, sequential clinical decision making, have been developed. From a patient's perspective an ATS is a sequence of treatments, ...

journal_title：Statistics in medicine

authors： Almirall D,Compton SN,Gunlicks-Stoessel M,Duan N,Murphy SA

更新日期：2012-07-30 00:00:00

abstract：:A general method is presented that allows the researcher to change statistical design elements such as the residual sample size during the course of an experiment, to include an interim analysis for early stopping when no formal rule for early stopping was foreseen, to increase or reduce the number of planned interim ...

journal_title：Statistics in medicine

authors： Müller HH,Schäfer H

更新日期：2004-08-30 00:00:00

abstract：:Most statistical methodology for phase III clinical trials focuses on the comparison of a single experimental treatment with a control. An increasing desire to reduce the time before regulatory approval of a new drug is sought has led to development of two-stage or sequential designs for trials that combine the defini...

journal_title：Statistics in medicine

authors： Stallard N,Todd S

更新日期：2003-03-15 00:00:00

abstract：:A targeted poll was undertaken to compare and contrast models of data monitoring of randomized clinical trials sponsored by the National Institutes of Health. In an attempt to represent the institutes which conduct clinical trials, twelve individuals were selected and asked to respond to a questionnaire specifically p...

journal_title：Statistics in medicine

authors： Geller NL,Stylianou M

更新日期：1993-03-01 00:00:00

abstract：:In this paper we present a simple method for constructing (1- alpha)100 per cent confidence intervals for binomial proportions with near nominal coverage for all underlying proportion parameters on the unit interval. This new method uses, with a slight modification, the standard normal approximation technique taught i...

journal_title：Statistics in medicine

authors： Borkowf CB

更新日期：2006-11-15 00:00:00

abstract：:This paper discusses design considerations and the role of randomization-based inference in randomized community intervention trials. We stress that longitudinal follow-up of cohorts within communities often yields useful information on the effects of intervention on individuals, whereas cross-sectional surveys can us...

journal_title：Statistics in medicine

authors： Gail MH,Mark SD,Carroll RJ,Green SB,Pee D

更新日期：1996-06-15 00:00:00

abstract：:This work is motivated by a longitudinal study of women and their ectopic pregnancy outcomes in Lund, Sweden. In this article, we review and apply the Liang-Zeger methodology to the Lund ectopic pregnancy data set. We further analyse the ectopic pregnancy data using conditional modelling approaches suggested by Rosner...

journal_title：Statistics in medicine

authors： Hadgu A,Koch G,Westrom L

更新日期：1997-11-15 00:00:00

abstract：:Many extensions of survival models based on the Cox proportional hazards approach have been proposed to handle clustered or multiple event data. Of particular note are five Cox-based models for recurrent event data: Andersen and Gill (AG); Wei, Lin and Weissfeld (WLW); Prentice, Williams and Peterson, total time (PWP-...

journal_title：Statistics in medicine

authors： Kelly PJ,Lim LL

更新日期：2000-01-15 00:00:00

abstract：:The introduction of potent antiretroviral therapies for treatment of HIV infection typically results in a dramatic reduction in plasma HIV RNA concentration, often to levels undetectable by current measurement practices. However, although a high proportion of patients achieve 'undetectability', many then experience a ...

journal_title：Statistics in medicine

authors： McKinnon EJ,James IR,John M,Mallal SA

更新日期：2003-02-15 00:00:00

abstract：:Repeated cross-sectional samples are common in national surveys of health like the National Health Interview Survey (NHIS). Because population health outcomes generally evolve slowly, pooling data across years can improve the precision of current-year annual estimates of disease prevalence and other health outcomes. P...

journal_title：Statistics in medicine

authors： Lockwood JR,McCaffrey DF,Setodji CM,Elliott MN

更新日期：2011-02-28 00:00:00

abstract：:We consider Cox proportional hazards regression when the covariate vector includes error-prone discrete covariates along with error-free covariates, which may be discrete or continuous. The misclassification in the discrete error-prone covariates is allowed to be of any specified form. Building on the work of Nakamura...

journal_title：Statistics in medicine

authors： Zucker DM,Spiegelman D

更新日期：2008-05-20 00:00:00

abstract：:Risk prediction models play an important role in prevention and treatment of several diseases. Models that are in clinical use are often refined and improved. In many instances, the most efficient way to improve a successful model is to identify subgroups for which there is a specific biological rationale for improvem...

journal_title：Statistics in medicine

authors： Biswas S,Arun B,Parmigiani G

更新日期：2014-05-20 00:00:00

abstract：:We extend the method proposed in a recent work by the Authors for trial-level general surrogate evaluation to allow combinations of biomarkers and provide a procedure for finding the "best" combination of biomarkers based on the absolute prediction error summary of surrogate quality. We use a nonparametric Bayesian mo...

journal_title：Statistics in medicine

authors： Gabriel EE,Sachs MC,Daniels MJ,Halloran ME

更新日期：2019-03-30 00:00:00

abstract：:Pooling biospecimens prior to performing lab assays can help reduce lab costs, preserve specimens, and reduce information loss when subject to a limit of detection. Because many biomarkers measured in epidemiological studies are positive and right-skewed, proper analysis of pooled specimens requires special methods. I...

journal_title：Statistics in medicine

authors： Mitchell EM,Lyles RH,Schisterman EF

更新日期：2015-07-30 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：:The recent revision of the Declaration of Helsinki and the existence of many new therapies that affect survival or serious morbidity, and that therefore cannot be denied patients, have generated increased interest in active-control trials, particularly those intended to show equivalence or non-inferiority to the activ...

journal_title：Statistics in medicine

authors： Rothmann M,Li N,Chen G,Chi GY,Temple R,Tsou HH

更新日期：2003-01-30 00:00:00

abstract：:The relationship between association and surrogacy has been the focus of much debate in the surrogate marker literature. Recently, the individual causal association (ICA) has been introduced as a metric of surrogacy in the causal inference framework, when both the surrogate and the true endpoint are normally distribut...

journal_title：Statistics in medicine

authors： Meyvisch P,Alonso A,Van der Elst W,Molenberghs G

更新日期：2020-11-20 00:00:00

abstract：:The Spearman (rho(s)) and Kendall (tau) rank correlation coefficient are routinely used as measures of association between non-normally distributed random variables. However, confidence limits for rho(s) are only available under the assumption of bivariate normality and for tau under the assumption of asymptotic norma...

journal_title：Statistics in medicine

authors： Rosner B,Glynn RJ

更新日期：2007-02-10 00:00:00

abstract：:The FDA Guidance, while highly appropriate for industry sponsored trials, need not be imposed on publicly (e.g. NIH) financed clinical trials. While the potential for conflicts of interest exist in the latter, they are in general manageable and pose an acceptable low risk of threatening the integrity of a study. Howev...

journal_title：Statistics in medicine

authors： Lachin JM

更新日期：2004-05-30 00:00:00

abstract：:A three-component, competing-risk mortality model, developed for animal survival data, fits human life table data for all ages over a range of mean life spans from 16 to 74 years. The competing risks are a novel exponentially-decreasing hazard, dominant during immaturity; a constant hazard, dominant during adulthood; ...

journal_title：Statistics in medicine

authors： Siler W

更新日期：1983-07-01 00:00:00

abstract：:Longitudinal designs are important in medical research and in many other disciplines. Complete longitudinal studies, in which each subject is evaluated at each measurement occasion, are often very expensive and motivate a search for more efficient designs. Recently developed statistical methods foster the use of inten...

journal_title：Statistics in medicine

authors： Helms RW

更新日期：1992-10-01 00:00:00

abstract：:Comparative Poisson trials of prophylactic interventions, such as vaccines, can be lengthy and costly. We evaluate two easily implemented approaches to reduce numbers of disease cases and person years of follow up (N(u+t)) for comparative Poisson trials with fixed numbers of cases (T); (i) altering k the portion of N(...

journal_title：Statistics in medicine

authors： Hoover DR

更新日期：2004-04-30 00:00:00

abstract：:In the medical literature, hundreds of prediction models are being developed to predict health outcomes in individuals. For continuous outcomes, typically a linear regression model is developed to predict an individual's outcome value conditional on values of multiple predictors (covariates). To improve model developm...

journal_title：Statistics in medicine

authors： Riley RD,Snell KIE,Ensor J,Burke DL,Harrell FE Jr,Moons KGM,Collins GS

更新日期：2019-03-30 00:00:00

abstract：:We provide a Bayesian analysis of data categorized into two levels of age (younger than 50 years, at least 50 years) and three levels of bone mineral density (normal, osteopenia, osteoporosis) for white females at least 20 years old in the third National Health and Nutrition Examination Survey. For the sample, the age...

journal_title：Statistics in medicine

authors： Nandram B,Liu N,Choi JW,Cox L

更新日期：2005-04-15 00:00:00

abstract：:Estimates of relative efficacy between alternative treatments are crucial for decision making in health care. Bayesian mixed treatment comparison models provide a powerful methodology to obtain such estimates when head-to-head evidence is not available or insufficient. In recent years, this methodology has become wide...

journal_title：Statistics in medicine

authors： Schmitz S,Adams R,Walsh C

更新日期：2013-07-30 00:00:00

abstract：:The U.S. Food and Drug Administration (FDA) has proposed new regulations that address the 'prescribability' and 'switchability' of new formulations of already-approved drugs. These new criteria are known, respectively, as population and individual bioequivalence. Two methods have been proposed in the bioequivalence li...

journal_title：Statistics in medicine

authors： McNally RJ,Iyer H,Mathew T

更新日期：2003-01-15 00:00:00

abstract：:The publication of Fisher's correspondence on statistics has shed new light on his views on randomization. Quotations from this correspondence and from other works of Fisher are used to illustrate the role of randomization in clinical trials. It is concluded that Fisher's views not only are coherent but, despite havin...

journal_title：Statistics in medicine

authors： Senn S

更新日期：1994-02-15 00:00:00

abstract：:Estimates of transmission probabilities for sexually transmitted diseases historically come from studies of uninfected individuals exposed to those with a high disease prevalence (for example, prostitutes). However, changes in sexual behaviour, much of which relates to concerns about AIDS, has made identification of p...

journal_title：Statistics in medicine

authors： Katz BP

更新日期：1992-03-01 00:00:00

abstract：:Equal allocation of patients to treatment in a randomized clinical trial may have disadvantages ethically if the new treatment is believed to be at least as beneficial as the standard treatment. Others have considered, in a non-sequential setting, unbalanced randomized designs which allocate fewer patients to the pote...

journal_title：Statistics in medicine

authors： Lesser ML

更新日期：1982-07-01 00:00:00