Estimating treatment effects in clinical crossover trials.

abstract：:When marketed lots of pharmaceutical products produce a number of out-of-specification (OOS) samples, it can be very disruptive. In some cases such lots must be recalled, at substantial expense. We present a model of the probability of OOS samples and show quantitatively how this probability depends on the underlying ...

journal_title：Journal of biopharmaceutical statistics

authors： Fairweather WR

更新日期：2003-08-01 00:00:00

abstract：:We propose an adaptive two-stage dose-response design where a prespecified adaptation rule is used to add and/or drop treatment arms between the stages. We extend the multiple comparison procedures-modeling (MCP-Mod) approach into a two-stage design. In each stage, we use the same set of candidate dose-response models...

journal_title：Journal of biopharmaceutical statistics

authors： Franchetti Y,Anderson SJ,Sampson AR

更新日期：2013-01-01 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abstract：:The Food and Drug Administration of the United States issued a draft guidance on adaptive design clinical trials in February 2010. This draft guidance has attracted a lot of attention because of the increasing interest in adaptive trials by the pharmaceutical industry in recent years.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 provide a set of formulas that allow the combination of separately performed analyses of population pharmacokinetic (PK) studies, without any further computational effort. More specifically, given the point estimates and uncertainties of two population PK analyses, the formulas provide the point estimates and uncer...

journal_title：Journal of biopharmaceutical statistics

authors： Dokoumetzidis A,Aarons L

更新日期：2008-01-01 00:00:00

abstract：:Administration of biological therapeutics can generate undesirable immune responses that may induce anti-drug antibodies (ADAs). Immunogenicity can negatively affect patients, ranging from mild reactive effect to hypersensitivity reactions or even serious autoimmune diseases. Assessment of immunogenicity is critical a...

journal_title：Journal of biopharmaceutical statistics

authors： Zhang J,Yu B,Zhang L,Roskos L,Richman L,Yang H

更新日期：2015-01-01 00:00:00

abstract：:A common question in clinical studies is how to use historical data from earlier studies, leveraging relevant information into the design and analysis of a new study. Bayesian approaches are particularly well-suited to this task, with their natural ability to borrow strength across data sources. In this paper, we prop...

journal_title：Journal of biopharmaceutical statistics

authors： Li JX,Chen WC,Scott JA

更新日期：2016-01-01 00:00:00

abstract：:The gold standard for evaluating treatment efficacy of a medical product is a placebo-controlled trial. However, when the use of placebo is considered to be unethical or impractical, a viable alternative for evaluating treatment efficacy is through a noninferiority (NI) study where a test treatment is compared to an a...

journal_title：Journal of biopharmaceutical statistics

authors： Gamalo-Siebers M,Gao A,Lakshminarayanan M,Liu G,Natanegara F,Railkar R,Schmidli H,Song G

更新日期：2016-01-01 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：:Dichotomizing a continuous biomarker is a common practice in medical research. Various methods exist in the literature for dichotomizing continuous biomarkers. The most widely adopted minimum p-value approach uses a sequence of test statistics for all possible dichotomizations of a continuous biomarker, and it chooses...

journal_title：Journal of biopharmaceutical statistics

authors： Su M,Fang L,Su Z

更新日期：2013-05-01 00:00:00

abstract：:In various pharmaceutical applications, repeated measurements are taken from each subject, and model parameters are estimated from the collected data. Examples include dose response modeling and PK/PD studies with serial blood sampling, among others. The quality of the information in an experiment is reflected in the ...

journal_title：Journal of biopharmaceutical statistics

authors： Gagnon R,Leonov S

更新日期：2005-01-01 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：: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：: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 sequential parallel comparison design (SPCD) is a two-stage design recommended for trials with possibly high placebo response. A drug-placebo comparison in the first stage is followed in the second stage by placebo nonresponders being re-randomized between drug and placebo. We describe how SPCD can be used in tria...

journal_title：Journal of biopharmaceutical statistics

authors： Wang JJ,Ivanova A

更新日期：2014-01-01 00:00:00

abstract：:The Wilcoxon-Mann-Whitney (WMW) test is the most commonly used nonparametric method to compare two treatments when the underlying distribution of the outcome variable is not normally distributed. In the presence of stratum effects, the van Elteren (vE) test, a stratified WMW test, can be used to adjust for the stratum...

journal_title：Journal of biopharmaceutical statistics

authors： Qu Y,Zhao YD,Rahardja D

更新日期：2008-01-01 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：:People exposed to certain diseases are required to be treated with a safe and effective dose level of a drug. In epidemiological studies to find out an effective dose level, different dose levels are applied to the exposed and a certain number of cures is observed. Negative binomial distribution is considered to fit o...

journal_title：Journal of biopharmaceutical statistics

authors： Roy M,Choudhury K,Islam MM,Matin MA

更新日期：2013-01-01 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：:During preclinical drug development, the immune system is specifically evaluated after prolonged treatment with drug candidates, because the immune system may be an important target system. The response of antibodies against a T-cell-dependent antigen is recommenced by the FDA and EMEA for the evaluation of immunosupp...

journal_title：Journal of biopharmaceutical statistics

authors： Shkedy Z,Straetemans R,Molenberghs G,Desmidt M,Vinken P,Goeminne N,Coussement W,Van Den Poel B,Bijnens L

更新日期：2005-01-01 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：:Multiple testing problems in regulatory applications are often more challenging than the problems of handling a set of mathematical symbols representing multiple null hypotheses under testing. In the union-intersection setting, it is important to define a family of null hypotheses relevant to the clinical questions at...

journal_title：Journal of biopharmaceutical statistics

authors： Hung HM,Wang SJ

更新日期：2009-01-01 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：: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：: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：:Bowker's test, a generalization of McNemar's test, performs well under the hypothesis of symmetry, but the estimator of variance used in the test is biased when the table is asymmetric and this calls into question the test's performance in non-null situations. We seek an alternative to Bowker's test in search of metho...

journal_title：Journal of biopharmaceutical statistics

authors： May WL,Johnson WD

更新日期：2001-02-01 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：: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：: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：: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：: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