Subgroup analyses in randomized clinical trials: statistical and regulatory issues.

abstract：:Multiple comparisons are commonly seen in clinical trials and many other fields. An example, which is the focus of this paper, is the comparison of several test treatments (possibly different doses of a compound) with placebo (control). It is well known that steps must be taken to control the type I error rate when mu...

journal_title：Journal of biopharmaceutical statistics

authors： Chen M,Kianifard F

更新日期：1997-07-01 00:00:00

abstract：:We assess the QT effect using an exposure-response model in a "thorough QT/QTc study" with a four-period crossover design in which the treatments are placebo, positive control, higher dose of investigational drug, and therapeutic dose of investigational drug. In the study, QTc interval values and the drug concentratio...

journal_title：Journal of biopharmaceutical statistics

authors： Hosmane B,Locke C,Chiu YL

更新日期：2010-05-01 00:00:00

abstract：:This paper addresses the problem of analyzing multivariate response with the variates having different distributions. We use the generalized estimating equations proposed by Prentice and Zhao (1) to estimate mean and covariance parameters. Wald statistics are used to test hypotheses about the parameters. Data from a t...

journal_title：Journal of biopharmaceutical statistics

authors： May WL,Johnson WD

更新日期：1996-05-01 00:00:00

abstract：:Clinical trials often use a binary "fold increase" endpoint defined according to the ratio of interval-censored measurement at end-of-study to that at baseline. We propose a simple yet principled analytic approach based on the linear mixed-effects model for interval-censored data for the analysis of such paired measur...

journal_title：Journal of biopharmaceutical statistics

authors： Xu Y,Lam KF,Ooi EE,Wilder-Smith A,Paton NI,Lee LS,Cheung YB

更新日期：2015-01-01 00:00:00

abstract：:The purpose of the research is to develop a statistical decision support algorithm for patients who may benefit from Adjuvant Cisplatin/Vinorelbine (ACT) and improve their survival rates. Genome-wide microarray data are used to identify feasible sets of genes and probe sets that constitute the gene signature. The data...

journal_title：Journal of biopharmaceutical statistics

authors： Moon H,Chao T,Ahn H

更新日期：2020-05-03 00:00:00

abstract：:This paper introduces exact permutation methods for use when there are independent clusters of data with arbitrary within-cluster correlation. To eliminate the problem of clustering, we randomly select a data point from each cluster and for this now independent data, and calculate our test statistic and the associated...

journal_title：Journal of biopharmaceutical statistics

authors： Follmann D,Fay M

更新日期：2010-07-01 00:00:00

abstract：:Sample size calculation formulas for testing equality, noninferiority, superiority, and equivalence based on odds ratio were derived under both parallel and one-arm crossover designs. An example concerning the study of odds ratio between a test compound (treatment) and a standard therapy (control) for prevention of re...

journal_title：Journal of biopharmaceutical statistics

authors： Wang H,Chow SC,Li G

更新日期：2002-11-01 00:00:00

abstract：:The design of a three-arm trial including the experimental treatment, an active reference treatment, and a placebo is recommended as a useful approach to the assessment of noninferiority of the experimental treatment. The inclusion of the placebo arm enables the assessment of assay sensitivity and internal validation,...

journal_title：Journal of biopharmaceutical statistics

authors： Hida E,Tango T

更新日期：2013-01-01 00:00:00

abstract：:Nonparametric methods are presented for the analysis of the two-treatment, two-period crossover design with multivariate response. After forming within-subject sums and differences, the usual tests, including those for carry-over effects and direct treatment effects, can be constructed using a multivariate analysis of...

journal_title：Journal of biopharmaceutical statistics

authors： Johnson WD,Grender JM

更新日期：1993-03-01 00:00:00

abstract：:A thorough QT trial is typically designed to test for two set of hypotheses. The primary set of hypotheses is for demonstrating that the test treatment will not prolong QT interval. The second set of hypotheses is to demonstrate the assay sensitivity of the positive control treatment in the study population. The conve...

journal_title：Journal of biopharmaceutical statistics

authors： Tsong Y

更新日期：2013-01-01 00:00:00

abstract：:Parameter estimation following an adaptive design or group sequential design has been extremely challenging due to potential random high from its face value estimate. In this paper, we introduce a new framework to model clinical trial data flow based on a marked point process (MPP). The MPP model allows us to use meth...

journal_title：Journal of biopharmaceutical statistics

authors： Luo X,Li M,Shih WJ,Ouyang P

更新日期：2012-01-01 00:00:00

abstract：:For approval of generic drugs, the U.S. Food and Drug Administration (FDA) requires the evidence of bioequivalence in average bioavailability be provided. This is based on the Fundmental Bioequivalence Assumption from FDA that if two drug products are shown to be bioequivalent, it is assumed that they are therapeutica...

journal_title：Journal of biopharmaceutical statistics

authors： Lu Y,Zhang ZZ,Chow SC

更新日期：2014-01-01 00:00:00

abstract：:A randomized, active-control clinical trial setting with the objective of testing noninferiority for a continuous response variable is considered. Noninferiority margin is based on the concept of preserving a certain fraction of the active control effect. Noninferiority is established if the ratio of the lower (upper)...

journal_title：Journal of biopharmaceutical statistics

authors： Chen M,Kianifard F,Dhar SK

更新日期：2006-05-01 00:00:00

abstract：:For the assessment of biosimilarity of biosimilar products, the United States (US) Food and Drug Administration (FDA) proposed a stepwise approach for providing the totality-of-the-evidence of similarity between a proposed biosimilar product and a US-licensed (reference) product. The stepwise approach starts with the ...

journal_title：Journal of biopharmaceutical statistics

authors： Wang T,Chow SC

更新日期：2017-01-01 00:00:00

abstract：:For noninferiority testing with the maximum allowable noninferiority margin being prespecified, one can perform valid statistical testing at the same alpha level for multiple noninferiority hypotheses with margins being smaller than this maximum margin. This is easily comprehensible because only one confidence level i...

journal_title：Journal of biopharmaceutical statistics

authors： Hung HM,Wang SJ

更新日期：2004-05-01 00:00:00

abstract：:We address the issue of analysis of clinical data generated by the bridging study conducted in the new region to evaluate the similarity for extrapolation of the foreign clinical data. A bridging study is usually conducted in the new region only after the test product is approved for commercial marketing in the origin...

journal_title：Journal of biopharmaceutical statistics

authors： Liu JP,Hsiao CF,Hsueh H

更新日期：2002-08-01 00:00:00

abstract：:Patient-reported outcomes are important for assessing the effectiveness of treatments in many disease areas. For this reason, many new instruments that capture patient-reported outcomes have been developed over the past several decades. With the development of each new instrument, there is the ensuing question of what...

journal_title：Journal of biopharmaceutical statistics

authors： Kirby S,Chuang-Stein C,Morris M

更新日期：2010-09-01 00:00:00

abstract：:The widely used distinction of Little and Rubin (1) about types of randomness for missing data presents difficulties in its application to dropouts in longitudinal repeated measurement studies. In its place, a new typology of randomness for dropouts is proposed that relies on using a survival model for the dropout pro...

journal_title：Journal of biopharmaceutical statistics

authors： Lindsey JK

更新日期：2000-11-01 00:00:00

abstract：:A test and a reference analytical method are usually compared for agreement based on paired data obtained from several independent subjects. Bias between two methods can be classified as constant and proportional. In this article, we provide an approach for maximum likelihood estimation of total bias between two metho...

journal_title：Journal of biopharmaceutical statistics

authors： Magari RT

更新日期：2004-11-01 00:00:00

abstract：:The van Elteren test, as a type of stratified Wilcoxon-Mann-Whitney test for comparing two treatments accounting for stratum effects, has been used to replace the analysis of variance when the normality assumption was seriously violated. The sample size estimation methods for the van Elteren test have been proposed an...

journal_title：Journal of biopharmaceutical statistics

authors： Zhao YD,Qu Y,Rahardja D

更新日期：2006-01-01 00:00:00

abstract：:We introduce the idea of a design to detect signals of efficacy in early phase clinical trials. Such a design features three possible decisions: to kill the compound; to continue with staged development; or to continue with accelerated development of the compound. We describe how such studies improve the trade-off bet...

journal_title：Journal of biopharmaceutical statistics

authors： Brown MJ,Chuang-Stein C,Kirby S

更新日期：2012-01-01 00:00:00

abstract：:As more biologic products are going off patent protection, the development of follow-on biologics products has received much attention from both biotechnology industry and the regulatory agencies. Unlike small-molecule drug products, the development of biologic products is very different and variable via the manufactu...

journal_title：Journal of biopharmaceutical statistics

authors： Hsieh TC,Chow SC,Liu JP,Hsiao CF,Chi E

更新日期：2010-01-01 00:00:00

abstract：:In literature, there are a few unified approaches to test proof of concept and estimate a target dose, including the multiple comparison procedure using modeling approach, and the permutation approach proposed by Klingenberg. We discuss and compare the operating characteristics of these unified approaches and further ...

journal_title：Journal of biopharmaceutical statistics

authors： Tang Y,Cai C,Sun L,He J

更新日期：2017-01-01 00:00:00

abstract：:Testing for noninferiority and equivalence between an experimental therapy and a standard therapy in terms of the ratio of binomial proportions is considered. New tests based on the Fieller-Hinkley distribution of the ratio of random variables are proposed. Restricted maximum likelihood estimates of the null variances...

journal_title：Journal of biopharmaceutical statistics

authors： Koti KM

更新日期：2007-01-01 00:00:00

abstract：:Historical control trials (HCTs) are frequently conducted to compare an experimental treatment with a control treatment from a previous study, when they are applicable and favored over a randomized clinical trial (RCT) due to feasibility, ethics and cost concerns. Makuch and Simon developed a sample size formula for h...

journal_title：Journal of biopharmaceutical statistics

authors： Zhu H,Zhang S,Ahn C

更新日期：2016-01-01 00:00:00

abstract：:This article discusses the design of a clinical trial where a new treatment will be compared to a control. For a specific type of endpoint, there are a wide variety of test statistics that can be used. Also, the investigator must decide how many patients to accrue in each arm as well as the duration of the study. Afte...

journal_title：Journal of biopharmaceutical statistics

authors： Lawrence J

更新日期：2002-05-01 00:00:00

abstract：:We studied the sensitivity of the number of unique design points and their placement, in Bayesian optimal designs for pharmacokinetic models, with respect to the magnitude of prior uncertainty. We used two and three-parameter pharmacokinetic models with fixed and mixed effects and two Bayesian optimal design criteria,...

journal_title：Journal of biopharmaceutical statistics

authors： Dokoumetzidis A,Aarons L

更新日期：2007-01-01 00:00:00

abstract：:The problem of testing treatment difference in the occurrence of a study endpoint in a randomized parallel-group comparative clinical trial with repeated responses under the assumption that the responses follow a bivariate zero-inflated Poisson (ZIP) distribution is considered. Likelihood ratio test for homogeneity of...

journal_title：Journal of biopharmaceutical statistics

authors： Yuen HK,Chow SC,Tse SK

更新日期：2015-01-01 00:00:00

abstract：:Four multidose animal carcinogenicity assay trend test procedures based on the chi-square, Hoel-Walburg, log-rank, and Peto procedures are compared under conditions of competing risks. A total of 42 different risk populations are simulated in which a simulated animal can contract one or more of five different tumor ty...

journal_title：Journal of biopharmaceutical statistics

authors： Graves TS

更新日期：1994-11-01 00:00:00

abstract：:In traditional dose-finding studies, dose-limiting toxicity (DLT) is determined within a fixed time observation window where DLT is often defined as a binary outcome. In the setting of oncology dose-finding trials, often patients in advanced stage of diseases are enrolled. Therefore, disease progression may occur with...

journal_title：Journal of biopharmaceutical statistics

authors： Biard L,Cheng B,Manji GA,Lee SM

更新日期：2020-09-15 00:00:00