IFCC Working Group Recommendations for Assessing Commutability Part 1: General Experimental Design.

Area of Science:

• Clinical Chemistry
• Laboratory Medicine
• Reference Materials

Background:

• Commutability is key for reference materials (RMs) to accurately reflect clinical sample (CS) behavior across different measurement procedures (MPs).
• Ensuring commutability is vital for RMs used in calibration, trueness control, and external quality assessment to guarantee reliable laboratory results.

Purpose of the Study:

• This report, Part 1 of a series, defines commutability and outlines essential experimental design components for its assessment.
• It aims to guide the selection of clinical samples, qualification of measurement procedures, and criteria for determining commutability.

Main Methods:

• The report details critical experimental design factors for commutability assessment.
• Key considerations include the selection of individual and pooled clinical samples (CSs) and the qualification of measurement procedures (MPs).
• Establishing clear criteria for determining commutability and generalizing findings are also addressed.

Main Results:

• Part 1 focuses on the foundational aspects of commutability assessment, defining the property and its importance.
• It lays the groundwork for subsequent parts by detailing the necessary experimental design considerations.

Conclusions:

• Proper assessment of reference material (RM) commutability is essential for the integrity of laboratory testing and clinical decision-making.
• This foundational report provides critical guidance on experimental design for commutability assessment, paving the way for robust statistical analyses in subsequent parts.