The importance of being fit for purpose

Significance of the Topic

Method validation and verification underpin the reliability of analytical measurements, which support critical decisions in healthcare, industry, environmental monitoring and more. Ensuring methods are ‘fit for purpose’ minimizes economic losses, safeguards public health and strengthens legal defensibility of results.

Objectives and Study Overview

This study outlines the rationale and process for demonstrating that laboratory methods meet defined performance requirements. It reviews guidance from the Eurachem Guide, illustrating how laboratories translate customer needs into analytical criteria and verify whether methods satisfy uncertainty, cost and time constraints.

Methodology and Instrumentation

A single-laboratory validation/verification approach is presented, covering planning, execution and reporting. Key performance characteristics include:

• Precision (repeatability, intermediate precision)
• Trueness
• Selectivity
• Working range
• Analytical sensitivity
• Limit of detection and quantification
• Ruggedness

Used Instrumentation

The guide does not prescribe specific instruments but provides principles applicable across standard analytical platforms. Laboratories select appropriate equipment based on target analytes, matrix and regulatory requirements.

Main Results and Discussion

The Eurachem Guide delivers practical tools:

• Definitions and rationale for each performance characteristic
• Experimental designs with statistical evaluation tables
• Templates for planning, recording and reporting validation/verification studies
• Guidance for incorporating validation data into internal quality control schemes

The discussion emphasizes reduced workload for standard methods versus in-house developments and the importance of addressing sampling where applicable.

Benefits and Practical Applications

Validated and verified methods enhance confidence in analytical data, facilitate regulatory compliance and support consistent quality control across laboratories. This leads to informed decision-making in trade, public health, environmental assessment and forensic analysis.

Future Trends and Potential Applications

Ongoing developments are likely to include:

• Automation of validation protocols and digital data management
• Integration of advanced statistical and chemometric tools
• Greater emphasis on inter-laboratory comparisons and proficiency testing
• Application of AI for dynamic method optimization

Conclusion

Method validation and verification are essential for ensuring analytical methods meet defined performance criteria. The structured guidance provided by the Eurachem Guide supports laboratories in delivering reliable, regulatory-compliant results while optimizing resource use.

Reference

1. Cantwell H (ed.), Eurachem Guide: The Fitness for Purpose of Analytical Methods, 3rd ed., Eurachem, 2025.
2. Barwick V (ed.), Planning and Reporting Method Validation Studies, Supplement to Eurachem Guide, 2nd ed., Eurachem, 2025.
3. Cantwell H (ed.), Blanks in Method Validation, Supplement to Eurachem Guide, 2nd ed., Eurachem, 2025.
4. Ramsey MH, Rostron PD, Raposo FC (eds.), Validation of Measurement Procedures that Include Sampling, Eurachem, 1st ed., 2024.