Baseline refers to the starting point of a clinical trial, which serves as the reference for evaluating all subsequent changes. At this defined point in time, all relevant parameters—such as physical examinations, laboratory values, vital signs, and outcome assessments—are systematically recorded and documented. These baseline characteristics form the foundation for the subsequent statistical analysis and evaluation of treatment effects.
The accurate collection of baseline data is of critical importance for CROs, as it influences the validity of the entire study. All baseline assessments must be performed prior to the first administration of study medication and after obtaining informed consent. The quality of this data determines the significance of the statistical analyses and the interpretability of the results. Modern EDC systems therefore implement extensive plausibility checks for baseline data.
Baseline characterization requires particular attention in complex patient populations or rare diseases. In these cases, CROs must ensure that all relevant prognostic factors are captured to enable stratified analyses later on. Furthermore, baseline documentation must take the requirements of various regulatory authorities into account, as they may place different emphasis on the evaluation of study quality.