Bayesian assessment of the influence and interaction conditions in multipopulation tailoring clinical trials.

abstract：:With the use of finite mixture models for the clustering of a data set, the crucial question of how many clusters there are in the data can be addressed by testing for the smallest number of components in the mixture model compatible with the data. We investigate the performance of a resampling approach to this latter...

journal_title：Journal of biopharmaceutical statistics

authors： McLachlan GJ,Rathnayake SI

更新日期：2011-11-01 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

abstract：:Some statistical methods applied to in vitro diagnostic tests for the three primary indications (screening, diagnosis, and monitoring) are discussed. Various examples with practical statistical applications are presented, including test for k by k ordered categorical matched-pair data for screening of cervical cancer,...

journal_title：Journal of biopharmaceutical statistics

authors： Lao CS

更新日期：1997-11-01 00:00:00

abstract：:In clinical trials of drug development, patients are often followed for a certain period of time, and the outcome variables are measured at scheduled time intervals. The main interest of the trial is the treatment efficacy at a prespecified time point, which is often the last visit. In such trials, patient dropout is ...

journal_title：Journal of biopharmaceutical statistics

authors： Kong F,Chen YF,Jin K

更新日期：2009-11-01 00:00:00

abstract：:It is well known that there is strong relationship between HIV viral load and CD4 cell counts in AIDS studies. However, the relationship between them changes during the course of treatment and may vary among individuals. During treatments, some individuals may experience terminal events such as death. Because the term...

journal_title：Journal of biopharmaceutical statistics

authors： Lu T,Wang M,Liu G,Dong GH,Qian F

更新日期：2016-01-01 00:00:00

abstract：:Highly clustered count data are commonly seen in medical device clinical studies such as cardiac rhythm management. For instance, anti-arrhythmia shocks delivered from an implantable cardioverter-defibrillator (ICD) often occur as "storms", i.e., multiple shocks within a short period of time. There are unique challeng...

journal_title：Journal of biopharmaceutical statistics

authors： Wang ZJ

更新日期：2008-01-01 00:00:00

abstract：:An attractive application of expression technologies is to predict drug efficacy or safety using expression data of biomarkers. To evaluate the performance of various classification methods for building predictive models, we applied these methods on six expression datasets. These datasets were from studies using micro...

journal_title：Journal of biopharmaceutical statistics

authors： Man MZ,Dyson G,Johnson K,Liao B

更新日期：2004-11-01 00:00:00

abstract：:Classification measures play essential roles in the assessment and construction of classifiers. Hence, determining how to prevent these measures from being affected by individual observations has become an important problem. In this paper, we propose several indexes based on the influence function and the concept of l...

journal_title：Journal of biopharmaceutical statistics

authors： Ke BS,Chiang AJ,Chang YI

更新日期：2018-01-01 00:00:00

abstract：:The purpose of this paper is to describe, illustrate, and compare a number of different approaches to the analysis of repeated binary and categorical data. These approaches include empirical generalized least squares and generalized estimating equations, as well as traditional log-linear modeling methods. It is shown ...

journal_title：Journal of biopharmaceutical statistics

authors： Kenward MG,Jones B

更新日期：1992-01-01 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：:In a clinical dose finding study with active control a new drug with several dose levels is compared with an active comparator drug. The main focus of such studies often lies on the estimation of a target dose that leads to the same efficacy as the control. This article investigates the finite sample properties of the...

journal_title：Journal of biopharmaceutical statistics

authors： Helms HJ,Benda N,Friede T

更新日期：2015-01-01 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：: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

abstract：:Bayesian decision procedures have already been proposed for and implemented in Phase I dose-escalation studies in healthy volunteers. The procedures have been based on pharmacokinetic responses reflecting the concentration of the drug in blood plasma and are conducted to learn about the dose-response relationship whil...

journal_title：Journal of biopharmaceutical statistics

authors： Whitehead J,Zhou Y,Hampson L,Ledent E,Pereira A

更新日期：2007-01-01 00:00:00

abstract：:Due to the potential impact of ethnic factors on clinical outcomes, the global registration of a new treatment is challenging. China and Japan often require local trials in addition to a multiregional clinical trial (MRCT) to support the efficacy and safety claim of the treatment. The impact of ethnic factors on the t...

journal_title：Journal of biopharmaceutical statistics

authors： Huang Q,Chen G,Yuan Z,Lan KK

更新日期：2012-09-01 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：:ETRANK is a statistical software which uses nonparametric (randomization) technique to analyze incomplete repeated measures data, where the pattern of withdrawal is treatment related. This stand alone program is written in C, presently runs in MS-DOS, and a Windows version is in development. The program has been devel...

journal_title：Journal of biopharmaceutical statistics

authors： Entsuah R

更新日期：1996-11-01 00:00:00

abstract：:In 1968 the Food and Drug Administration (FDA) established the Adverse Event Reporting System (AERS) database containing data on adverse events (AEs) reported by patients, health care providers, and other sources through a spontaneous reporting system. FDA uses AERS for monitoring the safety of the drugs on the market...

journal_title：Journal of biopharmaceutical statistics

authors： Huang L,Zalkikar J,Tiwari RC

更新日期：2013-01-01 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：:I review the designs available for Phase I dose-finding studies of chemotherapeutic agents in cancer patients. The designs are based on the assumption that both efficacy and toxicity increase with dose, and thus attempt to minimize the number of patients treated at low doses, and also to minimize the chance that patie...

journal_title：Journal of biopharmaceutical statistics

authors： Potter DM

更新日期：2006-01-01 00:00:00

abstract：:Clinical trials with data-driven decision rules often pursue multiple clinical objectives such as the evaluation of several endpoints or several doses of an experimental treatment. These complex analysis strategies give rise to "multivariate" multiplicity problems with several components or sources of multiplicity. A ...

journal_title：Journal of biopharmaceutical statistics

authors： Kordzakhia G,Dmitrienko A,Ishida E

更新日期：2018-01-01 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：:During a clinical trial, balancing statistical and ethical considerations are important. Response-adaptive randomization methods use the information from past patients to increase the probability of the next patient receiving the better treatment while avoiding the statistical concern of selection bias. We compared th...

journal_title：Journal of biopharmaceutical statistics

authors： Piccorelli AV,Fraker SA

更新日期：2018-01-01 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：:Sample size adjustment at an interim analysis can mitigate the risk of failing to meet the study objective due to lower-than-expected treatment effect. Without modification to the conventional statistical methods, the type I error rate will be inflated, primarily caused by increasing sample size when the interim obser...

journal_title：Journal of biopharmaceutical statistics

authors： Chen YHJ,Yuan SS,Li X

更新日期：2018-01-01 00:00:00

abstract：:Although asymptotically, the empirical covariance estimator is consistent and robust with respect to the selection of the working correlation matrix, when the sample size is small, its bias may not be negligible. This article proposes a small sample correction for the empirical covariance estimator in general Gaussian...

journal_title：Journal of biopharmaceutical statistics

authors： Fan C,Zhang D,Zhang CH

更新日期：2012-01-01 00:00:00

abstract：:When performing a pivotal clinical trial, it may be of interest to assess the probability of success (PoS) of that trial. Initially evaluated when the trial is designed, PoS can be updated as the trial progresses and new information about the drug effect becomes available. Such information can be external to the trial...

journal_title：Journal of biopharmaceutical statistics

authors： Rufibach K,Jordan P,Abt M

更新日期：2016-01-01 00:00:00

abstract：:Predictive probability is particularly useful in aiding a decision-making process related to drug development. This is especially true for decisions occurring as the result of interim analyses of clinical trials. Examples of clinical trial applications of Bayesian predictive probability and the use of the beta-binomia...

journal_title：Journal of biopharmaceutical statistics

authors： Johns D,Andersen JS

更新日期：1999-03-01 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：: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