Master Protocols for Clinical Trials

Part 1: Basket & Umbrella Trial Designs Introduction As the clinical research landscape becomes ever more complex and interdisciplinary alongside an evolving genomic and biomolecular understanding of disease, the statistical design component that underpins this research must adapt to accommodate this. Accuracy of evidence and speed with which novel therapeutics are brought to market remain hurdles to be surmounted. While efficacy studies or non-inferiority clinical trials in the drug development space traditionally only included broad disease states usually with patients randomised to a dual arm of new treatment compared to an existing standard treatment. Due to patient biomarker heterogeneity, effective…
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Simpson’s Paradox: the perils of hidden bias.

How Simpson’s Paradox Confounds Research Findings And Why Knowing Which Groups To Segment By Can Reverse Study Findings By Eliminating Bias. Introduction   The misinterpretation of statistics or even the "mis"-analysis of data can occur for a variety of reasons and to a variety of ends. This article will focus on one such phenomenon contributing to the drawing of faulty conclusion from data – Simpson’s Paradox. At times a situation arises where the outcomes of a clinical research study depict the inverse of expected (or essentially correct) outcomes. Depending upon the statistical approach, this could affect means, proportions or relational trends…
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Latent Variable Modelling And The Chi Squared Exact Fit Statistic

Latent variable modelling and the chi squared exact fit statistic Latent variable models are exploratory statistical models used extensively throughout clinical and experimental research in medicine and the life sciences in general. Psychology and neuroscience are two key sub-disciplines where latent variable models are routinely employed to answer a myriad of research questions from the impact of personality traits on success metrics in the workplace (1) to measuring inter-correlated activity of neural populations in the human brain based on neuro-imaging data (2). Through latent variable modelling, dispositions, states or process which must be inferred rather than directly measured can be…
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Do I need a Biostatistician?

".... half of current published peer-reviewed clinical research papers ... contain at least one statistical error... When just surgical related papers were analysed, 78% were found to contain statistical errors." Peer reviewed published research is the go to source for clinicians and researchers to advance their knowledge on the topic at hand. It also currently the most reliable way available to do this. The rate of change in standard care and exponential development and implementation of innovative treatments and styles of patient involvement makes keeping up with the latest research paramount. (1) Unfortunately, almost half of current published peer-reviewed clinical…
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Transforming Skewed Data

​​Innumerable statistical tests exist for application in hypothesis testing based on the shape and nature of the pertinent variable’s distribution. If however the intention is to perform a parametric test - such as ANOVA, Pearson’s correlation or some types of regression - the results of such a test will be more valid if the distribution of the dependent variable(s) approximates a Gaussian (normal) distribution and the assumption of homoscedasticity is met. In reality data often fails to conform to this standard, particularly in cases where the sample size is not very large. As such, data transformation can serve as a…
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Accessing Data Files when Using SAS via Citrix Receiver

 ​A SAS licence can be prohibitively expensive for many use cases. Installing the software can also take up a surprising amount of hard disk space and memory. For this reason many individuals with light or temporary usage needs choose to access a version of SAS which is licenced to their institution and therefore shared across many users. Are you trying unsuccessfully to access an SAS remotely via your institution using Citrix receiver? This step-by-step guide might help. SAS syntax can differ based on whether a remote versus local server is used. An example of a local server is the computer you…
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