The importance of being fit for purpose

Importance of the Topic

Millions of analytical measurements are performed daily in laboratories worldwide to support trade, healthcare, food safety, environmental monitoring and forensic investigations. Errors in measurement can lead to substantial economic losses, legal penalties or health risks. Ensuring that each analytical method is fit for its intended purpose is critical to generate reliable data and support informed decision-making.

Aim and Overview of the Article

This article introduces the concept of method validation and verification as defined by Eurachem. It explains why laboratories must demonstrate that their analytical procedures meet predefined performance requirements. The text outlines a structured approach for planning, executing and reporting validation studies to confirm ‘fitness for purpose’.

Methodology and Instrumentation

Method validation/verification follows a single-laboratory workflow: translating the customer’s analytical problem into specific performance criteria, evaluating key characteristics, and comparing results against acceptance goals.

• Performance characteristics include precision (repeatability and intermediate precision), trueness, selectivity, working range, analytical sensitivity, limit of detection, limit of quantification and ruggedness.
• Sampling and subsampling steps are validated when they form part of the overall procedure.

Although no specific instruments are listed in the source, standard analytical platforms (e.g., chromatography, spectroscopy, titrimetry) are implied. Statistical tools are applied to assess each performance parameter and generate validation reports.

Main Results and Discussion

The Eurachem Guide provides practical guidance, including:

• A clear description of validation concepts and terminology.
• Templates for planning and recording experimental designs.
• Quick-reference tables with recommended experiments and statistical evaluation methods for each performance characteristic.
• Advice on integrating validation data into internal quality control schemes.

This systematic approach enables laboratories to generate credible evidence that methods fulfill analytical requirements, facilitating regulatory compliance and customer confidence.

Benefits and Practical Application of the Method

• Improves reliability of measurement results and reduces uncertainty.
• Supports evidence-based decisions in quality assurance, regulatory submissions and legal contexts.
• Optimizes resource use by tailoring validation efforts to application-specific risks and requirements.
• Provides a documented framework for ongoing method performance monitoring.

Future Trends and Possible Uses

• Adoption of digital and AI-driven tools for automated validation planning, data collection and statistical analysis.
• Expansion of validation principles to on-line and real-time monitoring systems.
• Greater emphasis on multi-laboratory and inter-laboratory validation exercises to support harmonization of methods.
• Integration of sampling validation for complex matrices in environmental and food analysis.

Conclusion

Method validation and verification are essential steps to ensure analytical methods deliver trustworthy results. The Eurachem Guide offers a comprehensive, user-friendly framework that helps laboratories translate customer needs into validated procedures, enhancing data quality, regulatory compliance and operational efficiency.

Reference

1. H. Cantwell (ed.) Eurachem Guide: The Fitness for Purpose of Analytical Methods – A Laboratory Guide to Method Validation and Related Topics, 3rd ed., Eurachem, 2025.
2. V. Barwick (ed.) Planning and Reporting Method Validation Studies – Supplement to Eurachem Guide on the Fitness for Purpose of Analytical Methods, 2nd ed., Eurachem, 2025.
3. H. Cantwell (ed.) Blanks in Method Validation – Supplement to Eurachem Guide on The Fitness for Purpose of Analytical Methods, 2nd ed., Eurachem, 2025.
4. M. H. Ramsey, P. D. Rostron, F. C. Raposo (eds.) Eurachem/EUROLAB/CITAC/Nordtest/AMC Guide: Validation of Measurement Procedures that Include Sampling, 1st ed., Eurachem, 2024.