Survival analysis and prognosis for dementia patients.

abstract：:Bayesian statistical methodology has been used for more than 10 years in medical device premarket submissions to the U.S. Food and Drug Administration (FDA). A complete list of the publicly available information associated with these FDA applications is presented. In addition to the increasing number of Bayesian metho...

journal_title：Journal of biopharmaceutical statistics

authors： Campbell G

更新日期：2011-09-01 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：:In clinical trials, it is important to set up a design to reach a decision on effectiveness of a drug in treating a disease with the loss of the minimum number of patients. Group sequential designs are very beneficial on this point. However, the proportional hazards assumption must hold to work under a group sequentia...

journal_title：Journal of biopharmaceutical statistics

authors： Demirhan H,Demirhan YP,Bacanli S

更新日期：2013-03-11 00:00:00

abstract：:Noninferiority multiregional clinical trials (MRCTs) have recently received increasing attention in drug development. While a major goal in an MRCT is to estimate the global treatment effect, it is also important to assess the consistency of treatment effects across multiple regions. In this paper, we propose an intui...

journal_title：Journal of biopharmaceutical statistics

authors： Diao G,Zeng D,Ibrahim JG,Rong A,Lee O,Zhang K,Chen Q

更新日期：2017-01-01 00:00:00

abstract：:Dunnett's many-to-one test is used frequently today, especially in dose-finding studies. Using Dunnett's test, the Type I error level for the comparison between the raw mean of the control and the raw means of the study drug groups can be exactly calculated for the normal data. However, this computability depends on t...

journal_title：Journal of biopharmaceutical statistics

authors： Shun Z,Silverberg A,Chang CK,Ouyang P

更新日期：2003-02-01 00:00:00

abstract：:Sample size calculation based on normal approximations is often associated with the loss of statistical power for a single-arm trial with a time-to-event endpoint. Recently, Wu (2015) derived the exact variance for the one-sample log-rank test under the alternative and showed that a single-arm one-stage study based on...

journal_title：Journal of biopharmaceutical statistics

authors： Shan G

更新日期：2020-09-02 00:00:00

abstract：:The ICH E14 guidance (ICH, 2005) recommend that a concurrent positive control should be included in a thorough QTc clinical trial to validate the study. The ICH E14 guidance (ICH, 2005) state that "The positive control should have an effect on the mean QTc interval of about 5 ms (i.e., an effect that is close to the Q...

journal_title：Journal of biopharmaceutical statistics

authors： Zhang J

更新日期：2008-01-01 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：:Receptor occupancy (RO) PET is a non-invasive way to determine drug on target. Given the complexity of procedures, long acquisition times, and high cost, ligand displacement imaging trials often have a limited size and produce sparse RO results over the time course of the blocking drug. To take the best advantage of t...

journal_title：Journal of biopharmaceutical statistics

authors： Vandenhende F,Renard D,Nie Y,Kumar A,Miller J,Tauscher J,Witcher J,Zhou Y,Wong DF

更新日期：2008-01-01 00:00:00

abstract：:In confidence interval estimation of the difference between two proportions with overdispersion due to positive correlations, the usual asymptotic normality-based method generally has lower coverage rates than desired, especially when sample size is moderate. Applying the concept of effective sample size to existing m...

journal_title：Journal of biopharmaceutical statistics

authors： Chen C,Li J,Zhou Z

更新日期：2004-05-01 00:00:00

abstract：:Rubinstein et al. presented a procedure for determining the required duration of accrual for a clinical trial comparing the survival distributions of two treatments using a classical hypothesis testing formulation. Here their testing procedure is modified in two ways. First, the asymptotic variances used in computatio...

journal_title：Journal of biopharmaceutical statistics

authors： Bristol DR

更新日期：1993-09-01 00:00:00

abstract：:Frequentist design for two-arm randomized Phase II clinical trials with outcomes from the exponential dispersion family was proposed previously, where the total sample sizes are minimized under multiple constraints on the standard errors of the estimated group means and their difference. This design was generalized fr...

journal_title：Journal of biopharmaceutical statistics

authors： Jiang W,Wick JA,He J,Mahnken JD,Mayo MS

更新日期：2018-01-01 00:00:00

abstract：:Pressures for rapid drug development, especially for treatments that may affect public health significantly, drive a need to reconsider what is necessary to establish the "substantial evidence" of efficacy and safety required for regulatory approval. The concept of substantial evidence of effect can be stated fairly s...

journal_title：Journal of biopharmaceutical statistics

authors： Gould AL

更新日期：2002-02-01 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：:Statistical methodologies for human abuse potential studies are rarely evaluated. Human abuse potential studies assess whether test drugs produce positive and negative subjective responses on abuse-related measures using volunteers with histories of recreational drug use. These studies typically have a randomized, dou...

journal_title：Journal of biopharmaceutical statistics

authors： Chen L,Bonson KR

更新日期：2013-03-11 00:00:00

abstract：:Analyses of multicenter trials consider the estimated treatment effect differences of the individual centers and combine them into an estimate of the overall treatment effect. There has been much debate in the literature concerning the best way to combine these treatment effect differences. We emphasize that first of ...

journal_title：Journal of biopharmaceutical statistics

authors： Dragalin V,Fedorov V,Jones B,Rockhold F

更新日期：2001-11-01 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：:A framework is proposed for making quality predictions in situations for which only systematically inaccurate data are available. The predictions are based on the systematically inaccurate data, complete data from similar situations, and expert knowledge. The proposed predictive model is well suited to functional data...

journal_title：Journal of biopharmaceutical statistics

authors： Haaland B,Chiang AY

更新日期：2014-01-01 00:00:00

abstract：:The adverse events data of randomized clinical trials are often analyzed based on either crude incidence rates or exposure-adjusted incidence rates. These rates do not adequately account for an individual patient's profile of adverse events over the study period when an individual may remain in the trial after experie...

journal_title：Journal of biopharmaceutical statistics

authors： Siddiqui O

更新日期：2009-09-01 00:00:00

abstract：:We consider the problem of estimating a biomarker-based subgroup and testing for treatment effect in the overall population and in the subgroup after the trial. We define the best subgroup as the subgroup that maximizes the power for comparing the experimental treatment with the control. In the case of continuous outc...

journal_title：Journal of biopharmaceutical statistics

authors： Joshi N,Fine J,Chu R,Ivanova A

更新日期：2019-01-01 00:00:00

abstract：:The Youden index, a main summary index for the receiver operating characteristic (ROC) curve, is a comprehensive measurement for the effectiveness of a diagnostic test. For a continuous-scale diagnostic test, the optimal cut point for positive disease is the cut point leading to the maximization of the sum of sensitiv...

journal_title：Journal of biopharmaceutical statistics

authors： Zhou H,Qin G

更新日期：2012-01-01 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：: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：:As more biologic products are going off patent protection, the development of follow-on biologic products (also known as biosimilars) has gained much attention from both the biotechnology industry and regulatory agencies. Unlike small molecules, the development of biologic products is not only more complicated but als...

journal_title：Journal of biopharmaceutical statistics

authors： Zhang N,Yang J,Chow SC,Chi E

更新日期：2014-01-01 00:00:00

abstract：:An important application of confirmatory adaptive designs is the data-driven selection of treatment arms in multi-armed trials. A general methodology for adaptive designs is based on the combination testing principle. Using this principle, selection of treatment arms in multi-armed designs, recalculation of sample siz...

journal_title：Journal of biopharmaceutical statistics

authors： Wassmer G

更新日期：2011-07-01 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：:Stability testing is a procedure frequently used in the pharmaceutical industry to estimate the shelf life of a drug. Hereby, a standard problem of interest is whether or not to pool a given number of batches to assign a single shelf life for the combined batches. In this paper, we propose two modified methods for the...

journal_title：Journal of biopharmaceutical statistics

authors： Djira GD,Hothorn LA,Tsong Y

更新日期：2008-01-01 00:00:00

abstract：:The Food and Drug Administration of the United States issued a draft guidance on adaptive design clinical trials in February 2010. This draft guidance has attracted a lot of attention because of the increasing interest in adaptive trials by the pharmaceutical industry in recent years. In this paper, we report on highl...

journal_title：Journal of biopharmaceutical statistics

authors： Chuang-Stein C,Beltangady M

更新日期：2010-11-01 00:00:00

abstract：:A statistic, W, for measuring change from baseline is developed. Its distribution is found. Simulations using W and analysis of covariance (ANCOVA) are run and the results are compared. W is found to be less powerful than ANCOVA, yet is not seen to suffer some of the ill effects to which ANCOVA can fall prey, namely b...

journal_title：Journal of biopharmaceutical statistics

authors： Donahue RM

更新日期：1997-05-01 00:00:00

abstract：:The potency of a batch of drug product needs to meet a release limits at the time of release so that the potency at the end of shelf life remains above the lower registration limit (LRL). This article discusses two methods which determine the release limits such that the chance to fail LRL at the end of shelf life of ...

journal_title：Journal of biopharmaceutical statistics

authors： Wei GC

更新日期：1998-03-01 00:00:00