Biostatistics
Standard Deviation and Standard Error – What is the Difference?
When studying results of scientific publications one usually comes across standard deviations (SD) and standard errors (SE). However, even both measures are widely used the difference between them is not always clear to the readers. This article aims to clarify some important points and to provide a deeper understanding of SD and SE.
Intention-To-Treat (ITT) vs. Per-Protocol (PP) analysis: what to choose?
Differences between and characteristics of the Intention-To-Treat (ITT) vs. Per Protocol (PP) principles: which is the method of choice for the primary analysis of your clinical trial?
What to consider when planning the sample size for a non-interventional study
The determination of an "adequate" sample size is an essential part of the statistical planning process. Depending on your type of non-interventional study design and your specific study objectives, there are different approaches for the planning of your sample size [...]
Don’t panic: It’s only the Simpson’s Paradox
Your results on the overall patient level contradict results on the subgroup level? There is no need to panic. With a deeper look into the data, one can get to the bottom of this observation. [...]
Stuck in the middle – mean vs. median
The mean value of numerical data is without a doubt the most commonly used statistical measure. Anyone who has a basic statistical background knows how to calculate the (arithmetic) mean. However, sometimes the median is used as an alternative to the mean. [...]
Statistical testing in non-interventional studies (NIS)
In this article we would like to address the question whether it is useful to perform statistical testing in the context of a NIS, as it is often requested by the sponsor, and why, if tests are performed, we should handle their results with caution.