Strategies for changing the test statistic during a clinical trial.

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：: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：: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：:Laboratory data with a lower quantification limit (censored data) are sometimes analyzed by replacing non-quantifiable values with a single value equal to or less than the quantification limit, yielding possibly biased point estimates and variance estimates that are too small. Motivated by a three-period, three-treatm...

journal_title：Journal of biopharmaceutical statistics

authors： Karon JM,Wiegand RE,van de Wijgert JH,Kilmarx PH

更新日期：2015-01-01 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：:According to ICH Q6A (1999), a specification is defined as a list of tests, references to analytical procedures, and appropriate acceptance criteria, which are numerical limits, ranges, or other criteria for the tests described. For drug products, specifications usually consist of test methods and acceptance criteria ...

journal_title：Journal of biopharmaceutical statistics

authors： Dong X,Tsong Y,Shen M

更新日期：2015-01-01 00:00:00

abstract：:In recent years, multi-regional clinical trials (MRCT) that conduct clinical trials simultaneously in Asian Pacific region, Europe, and the United States have become very popular for global pharmaceutical development. The main purpose of multi-regional clinical trials is to shorten the time for pharmaceutical developm...

journal_title：Journal of biopharmaceutical statistics

authors： Ying L,Song F,Chow SC,Zeng N,Zheng J,Li X,Henry D,Sethuraman V

更新日期：2018-01-01 00:00:00

abstract：:In the early stages of traditional drug development, the frequency of dosing (e.g., QD, BID, etc.) is typically determined by the pharmacokinetic properties of a compound. After an appropriate dose frequency is chosen, the magnitude of dose is then evaluated via parallel-group dose-response trials. For some drugs, how...

journal_title：Journal of biopharmaceutical statistics

authors： Hafner KB,Ruberg SJ

更新日期：1996-07-01 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：: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 preclinical tumor xenograft experiments, the antitumor activity of the tested agents is often assessed by endpoints such as tumor doubling time, tumor growth delay (TGD), and log10 cell kill (LCK). In tumor xenograft literature, the values of these endpoints are presented without any statistical inference, which ig...

journal_title：Journal of biopharmaceutical statistics

authors： Wu J

更新日期：2011-05-01 00:00:00

abstract：:We would like to estimate the parameters of a dose-response function with the greatest precision as possible. For a two-parameter model, this is equivalent to minimizing the area of the confidence ellipsoid, i.e., a D-optimal design. Previous work on this particular model has included minimal designs. These designs ar...

journal_title：Journal of biopharmaceutical statistics

authors： Lupinacci PJ,Raghavarao D

更新日期：2000-02-01 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：:This article deals with seven special issues related to the assumptions, applicability, and practical use of formulas for calculating power or sample size, respectively, for comparative clinical trials with time-to-event endpoints, with particular focus on the well-known Freedman and Schoenfeld methods. All problems a...

journal_title：Journal of biopharmaceutical statistics

authors： Abel UR,Jensen K,Karapanagiotou-Schenkel I,Kieser M

更新日期：2015-01-01 00:00:00

abstract：:A method is proposed for the estimation of drug or toxicity potencies using in vitro data. A typical experiment in cancer research is presented where cells from a tumor-derived cell line were deposited as fixed volumes in 12-well cell culture plates. After waiting for 72 hours (for further growth), the wells were expo...

journal_title：Journal of biopharmaceutical statistics

authors： Le Chap T,Grambsch PM,Liu A

更新日期：2005-01-01 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：: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：:Sample size estimation (SSE) is an important issue in the planning of clinical studies. While larger studies are likely to have sufficient power, it may be unethical to expose more patients than necessary to answer a scientific question. Budget considerations may also cause one to limit the study to an adequate size t...

journal_title：Journal of biopharmaceutical statistics

authors： Wu PS,Lin M,Chow SC

更新日期：2016-01-01 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：: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：:One of the most critical decision points in clinical development is Go/No-Go decision-making after a proof-of-concept study. Traditional decision-making relies on a formal hypothesis testing with control of type I and type II error rates, which is limited by assessing the strength of efficacy evidence in a small isola...

journal_title：Journal of biopharmaceutical statistics

authors： Huang B,Talukder E,Han L,Kuan PF

更新日期：2019-01-01 00:00:00

abstract：:A mathematical model is described for selecting combinations of chemotherapeutic drugs in order to maximize antitumor dose intensity subject to constraints on toxicity to normal organ systems. Determination of which drugs to combine and in what proportions to combine them offers combinatorially huge numbers of possibi...

journal_title：Journal of biopharmaceutical statistics

authors： Simon R,Korn EL

更新日期：1991-01-01 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：: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：: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：: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：:Pharmaceutical product development culminates in confirmatory trials whose evidence for the product's efficacy and safety supports regulatory approval for marketing. Regulatory agencies in countries whose patients were not included in the confirmatory trials often require confirmation of efficacy and safety in their p...

journal_title：Journal of biopharmaceutical statistics

authors： Gould AL,Jin T,Zhang LX,Wang WW

更新日期：2012-09-01 00:00:00

abstract：:In many clinical trials for chronic conditions a run-in period is used prior to randomization. Often, only those participants who meet certain criteria during the run-in phase go on to get randomized. The others, along with the information that they might have provided, are excluded from the study. This exclusion of t...

journal_title：Journal of biopharmaceutical statistics

authors： Berger VW,Vali B

更新日期：2011-03-01 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 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