Wilcoxon-Mann-Whitney test: stratify or not?

abstract：:Investigating the prevalence of a disease is an important topic in medical studies. Such investigations are usually based on the classification results of a group of subjects according to whether they have the disease. To classify subjects, screening tests that are inexpensive and nonintrusive to the test subjects are...

journal_title：Journal of biopharmaceutical statistics

authors： Tang ML,Qiu SF,Poon WY,Tang NS

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abstract：:The Food and Drug Administration of the United States issued a draft guidance on adaptive design clinical trials in February 2010. This draft guidance has attracted a lot of attention because of the increasing interest in adaptive trials by the pharmaceutical industry in recent years.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：:We present a new computational method for identifying regulated pathway components in transcript profiling (TP) experiments by evaluating transcriptional activity in the context of known biological pathways. We construct a graph representing thousands of protein functional relationships by integrating knowledge from p...

journal_title：Journal of biopharmaceutical statistics

authors： Pradines J,Rudolph-Owen L,Hunter J,Leroy P,Cary M,Coopersmith R,Dancik V,Eltsefon Y,Farutin V,Leroy C,Rees J,Rose D,Rowley S,Ruttenberg A,Wieghardt P,Sander C,Reich C

更新日期：2004-08-01 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：:The dose-response models for full agonists and for a particular type of partial agonist can be described by sigmoidal curves and bell-shaped curves, respectively. The methods currently used to evaluate the interaction of a full agonist and a partial agonist require a large number of experimental units and base their a...

journal_title：Journal of biopharmaceutical statistics

authors： Ghosh K,Shen ES,Arey BJ,López FJ

更新日期：1998-11-01 00:00:00

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：:The study of drug combinations has become important in drug development due to its potential for efficacy at lower, less toxic doses and the need to move new therapies rapidly into clinical trials. The goal is to identify which combinations are additive, synergistic, or antagonistic. Although there exists statistical ...

journal_title：Journal of biopharmaceutical statistics

authors： Fang HB,Tian GL,Li W,Tan M

更新日期：2009-07-01 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：:We develop a Bayesian approach for estimating vaccine efficacy for susceptibility (VEs) and infectiousness (VEI) using outbreak size household data. Our method allows for heterogeneity in transmission probabilities due to factors that are related to individuals' characteristics, such as age, in addition to vaccination...

journal_title：Journal of biopharmaceutical statistics

authors： Davis XM,Waller LA,Haber M

更新日期：2006-01-01 00:00:00

abstract：:Failure to recognize the serious implications of heterogeneous correlations and disregard of the multiple test problem in interpreting the results from repeated measurements ANOVA of any single primary outcome measure can produce false-positive error rates that are more than five times the alpha level that is reported...

journal_title：Journal of biopharmaceutical statistics

authors： Overall JE,Doyle SR

更新日期：1996-03-01 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：: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：: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：:An integral part of routine health checkups involves laboratory measurements on various analytes in the blood. It is then common to compare the value of two consecutive measurements sampled at different times from the same patient. A "significant" change requires an action (additional sample and/or clinical action). T...

journal_title：Journal of biopharmaceutical statistics

authors： Cohen A,Doveh E,Umansky T

更新日期：2001-01-01 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：:Pharmacokinetic studies of drug and metabolite concentrations in the blood are usually conducted as crossover trials, especially in phases I and II. A longitudinal series of measurements is collected on each subject within each period. However, much of the dependence among such observations, within and between periods...

journal_title：Journal of biopharmaceutical statistics

authors： Lindsey JK,Wang J,Byrom WD,Jones B

更新日期：1999-08-01 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：: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：:In clinical trials, selection of appropriate study endpoints is critical for an accurate and reliable evaluation of safety and effectiveness of a test treatment under investigation. In practice, however, there are usually multiple endpoints available for measurement of disease status and/or therapeutic effect of the t...

journal_title：Journal of biopharmaceutical statistics

authors： Chow SC,Huang Z

更新日期：2019-01-01 00:00:00

abstract：:There is no consensus on determination of sample size in phase II clinical trials. The use of Bayesian decision theory has been proposed by Stallard (1), among others. In this article, optimal three-stage designs are obtained using decision theory. These are compared with procedures proposed by Schoenfeld (2), Ensign ...

journal_title：Journal of biopharmaceutical statistics

authors： Stallard N

更新日期：1998-07-01 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：: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：: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：: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：: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：:Hypoglycemia is a major safety concern for diabetic patients. Hypoglycemic events can be modeled based on time to recurrent events or count data. In this article, we evaluated a gamma frailty model with variance estimated by the inverse of observed Fisher information matrix, a gamma frailty model with the sandwich var...

journal_title：Journal of biopharmaceutical statistics

authors： Ma C,Qu Y,Fu H

更新日期：2020-05-18 00:00:00

abstract：:A useful testing strategy is proposed for a confirmatory phase III clinical trial. It consists of a combined test of superiority and test of equivalence, and it is easy to apply. By introducing the strategy, we can perform a post hoc analysis in a confirmatory experiment. Thus a more flexible decision will be possible...

journal_title：Journal of biopharmaceutical statistics

authors： Morikawa T,Yoshida M

更新日期：1995-11-01 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：:Due to the importance of precision medicine, it is essential to identify the right patients for the right treatment. Biomarkers, which have been commonly used in clinical research as well as in clinical practice, can facilitate selection of patients with a good response to the treatment. In this paper, we describe a b...

journal_title：Journal of biopharmaceutical statistics

authors： Diao G,Dong J,Zeng D,Ke C,Rong A,Ibrahim JG

更新日期：2018-01-01 00:00:00