Commutable specimens with minimal matrix effects are what make proficiency testing comparisons meaningful across methods and platforms.
External quality assessment only works if the material behaves like a patient sample. When it does not, differences between laboratories reflect the matrix rather than the measurement — and the scheme loses its diagnostic value.
What commutability means in practice
A commutable material produces the same relationship between measurement procedures as an authentic clinical specimen. Achieving this depends on how the base serum is collected, pooled and processed long before any target value is assigned.
Minimising matrix effects
- Careful donor pooling to reflect a realistic protein background
- Processing routes selected to avoid denaturation and artefacts
- Stabilisation strategies validated against real-time stability data
- Verification across multiple analytical platforms
Supporting method standardisation
Working with EQA providers worldwide, our aim is straightforward: materials that let a scheme distinguish genuine analytical performance from matrix noise, encourage method standardisation and ultimately support better patient outcomes.