Introduction
Method validation and verification are essential components of ISO/IEC 17025.
They ensure that laboratory methods produce accurate, reliable, and consistent results.
Despite this, the distinction between validation and verification is often misunderstood, leading to confusion and audit findings.
What Is Method Validation?
Method validation is required when:
- A new method is developed
- A non-standard method is used
- A method is significantly modified
Validation demonstrates that the method is fit for its intended purpose.
What Is Method Verification?
Verification applies when:
- A standard method is used
- The method has already been validated externally
Verification confirms that the laboratory can perform the method correctly under its own conditions.
Key Differences
| Validation | Verification |
|---|---|
| Proves method works | Confirms lab can perform it |
| Required for new methods | Required for standard methods |
| More extensive testing | Focused confirmation |
Common Gaps Observed
- Treating validation and verification the same
Same approach used without justification. - Insufficient data
Not enough data to demonstrate performance. - Lack of acceptance criteria
No clear definition of acceptable results. - Poor documentation
Results not traceable or structured. - No periodic review
Methods not reassessed over time.
Why These Issues Occur
- Misinterpretation of requirements
- Lack of statistical knowledge
- Over-reliance on templates
- Limited resources
What Effective Implementation Looks Like
- Clear distinction between validation and verification
- Defined performance parameters:
- Accuracy
- Precision
- Detection limits
- Documented acceptance criteria
- Sufficient and relevant data
- Ongoing monitoring
Practical, Step-by-Step Approach
Step 1: Determine Requirement
Is it validation or verification?
Step 2: Define Parameters
Based on method type.
Step 3: Establish Acceptance Criteria
Define what “acceptable” means.
Step 4: Perform Testing
Collect sufficient data.
Step 5: Evaluate Results
Compare against criteria.
Step 6: Document Clearly
Ensure traceability.
Step 7: Review Periodically
Update as needed.
Additional Considerations
- Consider real sample matrices
- Ensure staff competency
- Integrate with QC processes
Key Insight
Validation proves the method — verification proves your laboratory.
Conclusion
Understanding and applying validation and verification correctly improves data quality and supports compliance.