Statistics in Clinical Trials
Statistics is used for designing, analyzing and interpreting data in clinical trials
What is Statistical Analysis in Clinical Trials?
Most of us come across statistics in our daily life. This tool is used everywhere in society and across all fields, from economics to physics, from aquaculture research to knitting. As a researcher, you have likely taken at least one course in statistics during university and have applied statistics in your clinical research for publications.
Statistics is a tool that helps us transition from past observations to making predictions about the future. It is often divided into predictive analysis and causal cause-effect analysis. Prediction focuses on what is likely to happen without any intervention or manipulation, while causality examines what happens when active changes are made.
In clinical trials, causality and understanding the effects of an intervention are what interests clinical decision-makers. What will happen to my patient if I choose Treatment A versus Treatment B? Many factors may influence the patient’s outcome during treatment, but the aim is to make a decision that maximizes the likelihood of a positive outcome for the patient. One of the most common methods to address such clinical questions is by planning and conducting a randomized controlled clinical trial (RCT). In an RCT, patients are randomly assigned to one treatment group or another, and their outcomes are compared. However, many factors other than the treatment choice can affect patient outcomes. Therefore, it is essential to determine how much of the difference between groups is due to chance and how much is due to the treatment choice. This is the goal of statistical analysis.
Since statistics are central to analyzing and interpreting clinical trials, it is crucial to plan the analyses and interpretations before beginning patient recruitment. This is typically done in a trial protocol, which outlines the entire trial. In most clinical trial protocols, the statistical component plays a significant role. An essential part of this planning is determining the required sample size, which usually depends on the statistical analysis method to be used.
In addition to the trial protocol, a statistical analysis plan (SAP) is often created. This plan provides a more detailed account of the statistical analyses than the protocol. SAPs are increasingly requested by medical journals. They must be finalized before the analysis begins to ensure that the choice of analysis methods is not influenced by the study results.
Statistical Services
All statistical advisory services from the Clinical Trials Unit (CTU) are free of charge.
We can also conduct specific statistical tasks in your clinical trial and assist with statistics throughout all its phases. This includes designing the trial, calculating sample size, creating randomization lists, contributing to protocol development, drafting an analysis plan, programming analyses, interpreting results, and assisting with article writing. The conditions for such collaboration are formalized in an agreement, and the work is paid for by the project or trial group.
Our goal is to ensure that everything we deliver adheres to the international standards for "Good Statistical Practice." We follow the department’s quality management system, which includes a dedicated standard operating procedure (SOP) for statistical work in clinical trials. Our track record includes several publications in high-impact journals. We also adhere to the Vancouver authorship guidelines.
Our Team
A list of our team members can be found here (in Norwegian).