What is an external control arm?
An external control arm is a non-randomized comparator group that draws on data from real-world sources, historical clinical trials, or patient registries. It is used when a traditional randomized control group is not feasible or ethical, such as in rare diseases or certain oncology settings. These data are carefully selected and statistically adjusted to enable valid comparisons to the investigational treatment group.
Why are external control arms important in clinical research?
They support clinical trials in situations where recruiting or randomizing patients would be challenging or inappropriate. External control arms can reduce development timelines and broaden the applicability of results. However, their acceptance depends on the quality of the underlying data and the robustness of the methodology used to address potential biases.
