Linear structural equation model in analyzing quality-of-life-data from clinical trials.

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：: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：:Nonparametric versions of normal theory step-down multiple-test procedures for inferring minimum effective dose (see Tamhane et al. (1)) were developed and studied by Monte Carlo simulation. Two types of step-down testing procedures were examined. For both procedures, pairwise, linear, or Helmert contrasts of mean ran...

journal_title：Journal of biopharmaceutical statistics

authors： Sidik K,Morris RW

更新日期：1999-05-01 00:00:00

abstract：:Historical control trials (HCTs) are frequently conducted to compare an experimental treatment with a control treatment from a previous study, when they are applicable and favored over a randomized clinical trial (RCT) due to feasibility, ethics and cost concerns. Makuch and Simon developed a sample size formula for h...

journal_title：Journal of biopharmaceutical statistics

authors： Zhu H,Zhang S,Ahn C

更新日期：2016-01-01 00:00:00

abstract：:For noninferiority testing with the maximum allowable noninferiority margin being prespecified, one can perform valid statistical testing at the same alpha level for multiple noninferiority hypotheses with margins being smaller than this maximum margin. This is easily comprehensible because only one confidence level i...

journal_title：Journal of biopharmaceutical statistics

authors： Hung HM,Wang SJ

更新日期：2004-05-01 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：: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：: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：: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：:There are minimal standards for the processing of whole blood components, and to apply those standards requires a system of quality assurances. Excessive indications of failures in compliance trigger inspections and other remedial actions, but the demarcation of what is excessive is a critical issue. Issues of low vol...

journal_title：Journal of biopharmaceutical statistics

authors： Lachenbruch PA,Foulkes MA,Williams AE,Epstein JS

更新日期：2005-01-01 00:00:00

abstract：:In this study, a Bayesian approach was suggested to estimate a change-point according to a covariate threshold when some patients never experienced the event of interest. Gibbs sampler algorithm with latent binary cure indicators was used to simplify the implementation of Markov chain Monte Carlo method. Then, the acc...

journal_title：Journal of biopharmaceutical statistics

authors： Shamsi F,Baghestani AR,Binesh F

更新日期：2020-03-01 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：: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：: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 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：:The widely used distinction of Little and Rubin (1) about types of randomness for missing data presents difficulties in its application to dropouts in longitudinal repeated measurement studies. In its place, a new typology of randomness for dropouts is proposed that relies on using a survival model for the dropout pro...

journal_title：Journal of biopharmaceutical statistics

authors： Lindsey JK

更新日期：2000-11-01 00:00:00

abstract：:The aim of this article is to propose a multilevel combined model for repeated, hierarchical, and overdispersed time-to-event outcomes, extending the so-called combined model proposed by Molenberghs et al. (2010), and using three different estimation strategies: full likelihood, pseudo-likelihood, and Bayesian estimat...

journal_title：Journal of biopharmaceutical statistics

authors： Efendi A,Molenberghs G

更新日期：2013-01-01 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 use of adaptive methods in clinical development has become very popular in recent years due to its flexibility in modifying trial procedures and/or statistical procedures of on-going clinical trials. Modifications to trial procedures are usually documented by protocol amendments. However, the actual patient popula...

journal_title：Journal of biopharmaceutical statistics

authors： Chow SC,Shao J

更新日期：2005-01-01 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：: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：: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：:A new three-arm parallel design was recently proposed to investigate the biosimilarity between a biological product and a reference product by using the relative distance. The purpose of this article is to extend their results to binary endpoints for three popular metrics: the risk difference, the log relative risk, a...

journal_title：Journal of biopharmaceutical statistics

authors： Shin W,Kang SH

更新日期：2016-01-01 00:00:00

abstract：:Ratio of means (ROM) and difference of means (DOM) are often used in a superiority, noninferiority (NI), or average bioequivalence (ABE) test to evaluate whether the test mean is superior, NI, or equivalent to the reference (placebo or active control) mean. The literature provides recommendations regarding how to choo...

journal_title：Journal of biopharmaceutical statistics

authors： Sun W,Grosser S,Tsong Y

更新日期：2017-01-01 00:00:00

abstract：:Recently, a design was proposed for the Simultaneous Global Drug Development Program (SGDDP) to assess the impact of ethnic factors on the effect of a new treatment for a targeted ethnic (TE) population. It used weighted Z tests to combine the information collected from the TE and non-TE (NTE) subgroups in the SGDDP b...

journal_title：Journal of biopharmaceutical statistics

authors： Liu K,Yuan Z,Chen G,Huang Q,Wenrich J

更新日期：2015-01-01 00:00:00

abstract：:Drug-related side effects are one of the leading causes of death and illness in the developed world. Finding genes that modify drug response has the potential to significantly improve drug delivery, by identifying both individuals that can benefit from therapy and those at increased risk of harm. We present a simple a...

journal_title：Journal of biopharmaceutical statistics

authors： He M,Allen A

更新日期：2010-03-01 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：: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：:In method comparison and reliability studies, it is often important to assess agreement between multiple measurements made by different methods, devices, laboratories, observers, or instruments. For continuous data, the concordance correlation coefficient (CCC) is a popular index for assessing agreement between multip...

journal_title：Journal of biopharmaceutical statistics

authors： Barnhart HX,Lokhnygina Y,Kosinski AS,Haber M

更新日期：2007-01-01 00:00:00

abstract：:This paper addresses the problem of analyzing multivariate response with the variates having different distributions. We use the generalized estimating equations proposed by Prentice and Zhao (1) to estimate mean and covariance parameters. Wald statistics are used to test hypotheses about the parameters. Data from a t...

journal_title：Journal of biopharmaceutical statistics

authors： May WL,Johnson WD

更新日期：1996-05-01 00:00:00