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Open AccessSmartphone-assisted training with education for patients with hip and/or knee osteoarthritis (SmArt-E): study protocol for a multicentre pragmatic randomized controlled trial
Hip and knee osteoarthritis are associated with functional limitations, pain and restrictions in quality of life and the ability to work. Furthermore, with growing prevalence, osteoarthritis is increasingly ca...
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Article
Open AccessIs there a role for statistics in artificial intelligence?
The research on and application of artificial intelligence (AI) has triggered a comprehensive scientific, economic, social and political discussion. Here we argue that statistics, as an interdisciplinary scien...
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Article
Open AccessBlinded sample size re-estimation in a comparative diagnostic accuracy study
The sample size calculation in a confirmatory diagnostic accuracy study is performed for co-primary endpoints because sensitivity and specificity are considered simultaneously. The initial sample size calculat...
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Article
Open AccessSociodemographic aspects and health care-related outcomes: a latent class analysis of informal dementia care dyads
Studies revealed the importance to assess dementia care dyads, composed of persons with dementia and their primary informal caregivers, in a differentiated way and to tailor support services to particular livi...
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Article
Effectiveness and cost-effectiveness of an integrated care program for schizophrenia: an analysis of routine data
In Germany, a regional social health insurance fund provides an integrated care program for patients with schizophrenia (IVS). Based on routine data of the social health insurance, this evaluation examined the...
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Article
Sequential tests for non-proportional hazards data
In clinical trials survival endpoints are usually compared using the log-rank test. Sequential methods for the log-rank test and the Cox proportional hazards model are largely reported in the statistical liter...
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Book
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Chapter
Multiple Testing in Adaptive Designs
In this chapter we introduce the basic statistical methods to design and analyze clinical trials with hypotheses adaption at an interim analysis. We first describe the various sources of multiplicity which can...
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Chapter
Adaptive Designs with Survival Data
The designs with adaptive sample size modifications have been extended to survival data by several authors including application of the inverse normal method, the Fisher’s combination test approach, and some e...
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Chapter
Applications
This chapter focuses on specific characteristics and properties of group sequential tests in the most popular testing situation which we encounter in clinical trials. These are one- and two-sample tests for no...
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Chapter
Decision Tools for Adaptive Designs
Adaptive designs incorporate interim analyses where the interim data are used to decide whether to terminate or to continue the trial, and, if the trial is continued, how to design the remainder of the trial. ...
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Chapter
Procedures with Equally Sized Stages
In this chapter, we describe group sequential test procedures that are designed for equal sample sizes per stage of the group sequential trial. The procedures that were originally developed in the literature (...
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Chapter
Confidence Intervals, p-Values, and Point Estimation
Various approaches have been made to provide summary measures of evidence against the null hypothesis and in measures of the effect size. As p-values, point estimators and confidence intervals should serve as con...
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Chapter
Adaptive Group Sequential Tests
If the prior experience with the study treatments is insufficient for a persistent pre-specification of relevant and realistic treatment effects, the effect and corresponding sample sizes may be reassessed at ...
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Chapter
Estimation and p-Values for Two-Stage Adaptive Designs
With unblinded sample size adaptations the usual estimate such as the overall treatment difference can be biased and the usual confidence intervals may not have correct coverage probabilities. Thus, when provi...
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Chapter
Applications and Case Studies
In this chapter the general principle of adaptive combination tests is applied to two important situations in clinical trial. The first is the design with multiple treatment arms where, based on interim result...
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Chapter
Repeated Significance Tests
This chapter focuses on the conceptual background of the “classical” group sequential tests, i.e., the repeated significance testing approach. We start with a brief historical survey of group sequential tests....
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Chapter
Procedures with Unequally Sized Stages
In this chapter, we present group sequential test procedures that are specifically designed for unequally sized stages. We first describe the effect of using the decision boundaries designed for equally sized ...
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Article
New diagnostic markers in salivary gland tumors
Parotid gland tumors are a rare and heterogeneous entity. Molecular markers are sparse. The aim of the study was to identify new diagnostic markers in benign and malignant salivary tumors. A tissue microarray ...
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Article
A prospective, randomised, multicenter trial for surgical treatment of central retinal vein occlusion: results of the Radial Optic Neurotomy for Central Vein Occlusion (ROVO) study group
To compare the surgical outcomes and evaluate the effectiveness of two treatments for central retinal vein occlusion (CRVO), radial optic neurotomy (RON) and intravitreal triamcinolone (IVT), in comparison to ...
