In this paper we derive asymptotic x 2 - tests for general linear hypotheses on variance components using repeated variance components models. In two examples, the two-way nested classification model and the two-way crossed classification model with interaction, we explicitly investigate the...

In einer Re-Analyse der Blue Mountains Eye Study von Cumming, Mitchell und Leeder (1997) wird gezeigt, daß diese Studie keinen Beitrag zur Klärung des Kataraktrisikos von inhalativen Kortikoiden leistet. Akzeptiert man die Schlußweisen der Studie, so ergibt sich ein diffuses und zugleich aber...

A confidence interval for the between group variance is proposed which is deduced from Wald’s exact confidence interval for the ratio of the two variance components in the one-way random effects model and the exact confidence interval for the error variance resp. an unbiased estimator of the...

Concerning the actual significance level, we investigate the commonly used combined test procedures of meta-analysis, which contain the choice of the model, in which the analysis is carried out, and the commonly used tests for treatment effect in the fixed and random effects model, and some new...

In this paper we derive asymptotic x2-tests for general linear hypotheses on variance components using repeated variance components models. In two examples, the two-way nested classification model and the two-way crossed classification model with interaction, we explicitly investigate the...

Mit Hilfe einer numerischen Meta-Analyse wird gezeigt, daß in placebokontrollierten klinischen Studien mit vergleichbarem Studiendesign und vergleichbarer Zielvariable die Behandlung der funktionellen Dyspepsie mit einem Gastroprokinetikum (Cisaprid) erfolgreicher ist als mit...

Positive estimators of the between-group (between-study) variance are proposed. Explicit variance formulae for the estimators are given and approximate confidence intervals for the between-group variance are constructed, as our proposal to a long outstanding problem. By Monte Carlo simulation,...

Background: There are already many effective topical therapies available for use in the treatment of chronic plaque psoriasis. Unfortunately, these treatments are often associated with a not insignificant risk of undesirable effects. Objective and methods: In the randomized, prospective clinical...

For testing one-sided but also two-sided hypotheses concerning several treatment arms in group sequentially performed clinical trials with arbitrary outcome variables, a general learning method is considered that allows for a complete self-designing of the study. All information available prior...

In combining several tests of significance the individual test statistics are allowed to be dependent. By choosing the weighted inverse normal method for the combination, the dependency of the original test statistics is then characterized by a correlation of the transformed statistics. For this...