摘要:

In many clinical experiments multiple measurements are required for evaluation of the results. Several methods have been illustrated in the literature to deal with this problem. Some of these solve the problem of multiple testing bias just by looking at the significance of the most pronounced difference. On the other hand, some other methods are designed to take into account all the information available from an experiment. The purpose of this paper is to review these methods and compare the results they gave when applied to a clinical trial in which drug efficacy was assessed by 14 outcome measures.

ISSN:1054-3406    

DOI:10.1080/10543409608835127

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

摘要:

The proportional odds model is illustrated in the analysis of two efficacy scales used in a phase II clinical trial involving 81 schizophrenic patients. The proportional odds model preserves the discrete, ordinal nature of one of the scales. The analysis of this data suggested that the relation- ship between the two scales is not captured by a linear proportional odds model. A linear model and a piecewise linear model for the explanatory variable were therefore compared using likelihood-based analyses. Residuals from both models were compared. Predicted probabilities for the ordinal categories were constructed from the estimated model. Extensions and limitations of the model for interpretation of other trials and for the planning of future trials are discussed.

ISSN:1054-3406    

DOI:10.1080/10543409608835128

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

摘要:

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 covanance parameters. Wald statistics are used to test hypotheses about the parameters. Data from a two-group study of competing programs to increase memory recall in geriatric patients are analyzed. We are interested in determining whether there is a simultaneous increase in test scores with one variate being continuous and another being dichotomous. In a second example comparisons of before-and-after treatment serum cholesterol levels and number of snacks eaten per day are made in an experiment to determine efficacy of a program aimed at simultaneously reducing both measurements.

ISSN:1054-3406    

DOI:10.1080/10543409608835129

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

摘要:

Procedures for determining sample size in multivariate repeated measures experiments are discussed. The focus is on designs with either one group or two independent groups of subjects, the point of departure being multivariate repeated measures. Determination of the minimum sample size required is based on power considerations associated with Hotelling'sT2and theF-test. We first consider procedures for determining sample size assuming an arbitrary covariance matrix. The special case where we assume that the transformed data have a multivariate spherical covariance matrix is also considered. Tables of the minimum sample sizes required for several hypotheses from multivariate analysis are presented.

ISSN:1054-3406    

DOI:10.1080/10543409608835130

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

摘要:

Scheffe gave an exact solution to the problem of comparing two means from normal populations with unequal variances that is useful for general analysis of variance problems. The behavior of the usualt-statistic that assumes equal variances is contrasted to Satterthwaite's approximatet- statistic and Scheffe's method. An interesting relationship is uncovered between Scheffe's and Satterthwaite's solutions.

ISSN:1054-3406    

DOI:10.1080/10543409608835131

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

摘要:

The use of Lattice Square designs for estimating the relative potencies in a multiple bioassay is illustrated in this paper. The analysis is presented with and without recovery of inter-row and column information.

ISSN:1054-3406    

DOI:10.1080/10543409608835132

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

摘要:

A previous paper in this journal mistakenly attributes a proposal to me that I did not make. I clear up the confusion. I also bring reasons to believe that the simulation presented in that paper is not relevant.

ISSN:1054-3406    

DOI:10.1080/10543409608835133

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

ISSN:1054-3406    

DOI:10.1080/10543409608835134

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

ISSN:1054-3406    

DOI:10.1080/10543409608835135

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor

ISSN:1054-3406    

DOI:10.1080/10543409608835136

出版商:Marcel Dekker, Inc.    

年代:1996

数据来源: Taylor