31. März 2026
Fähzan Ahmad • 31. März 2026
Why detecting small changes is irrelevant if results are not stable

High sensitivity is meaningless without robustness
Modern assays are designed to detect even the smallest biological changes. While this increases analytical power, it also introduces a critical risk: highly sensitive systems often respond to noise as readily as they do to true biological effects.
Regulatory assessment prioritizes reliability over detectability.
The limitation of sensitivity
Sensitivity determines how small a change an assay can detect. However, detecting minor variations is not inherently valuable if those variations are inconsistent or influenced by external factors.
An assay that detects everything may not distinguish what actually matters.
Why robustness matters
Robustness ensures that results remain stable across varying conditions, operators, and experimental runs. It defines whether an observed effect reflects a true biological signal or a system-specific fluctuation.
Without robustness, sensitivity amplifies uncertainty rather than insight.
Regulatory perspective
Regulators expect assays to demonstrate consistent performance across conditions. This includes low variability, stable outputs, and clear separation between signal and background.
Highly sensitive but unstable assays are considered unreliable.
Conclusion
Sensitivity shows that an effect can be detected.
Robustness shows that the effect is real.
Without robustness, sensitivity becomes noise.








