Laboratory & Inspection Practice
Method validation vs verification: what assessors look for
How to decide between validation and verification and document it correctly.
Why this matters
Credible accreditation depends on consistent methods, clear decisions, and evidence that stands up to independent review. This publication translates essential expectations into practical steps so teams can prepare, communicate, and operate with confidence.
Key requirements and expectations
- Link technical competence to methods, equipment, and personnel.
- Demonstrate control of critical technical activities.
- Show traceability, uncertainty, and data integrity.
- Maintain records that prove repeatability and validity.
- Validation confirms a method is fit for intended use.
- Verification confirms implementation under local conditions.
- Acceptance criteria must be defined in advance.
Evidence and records to prepare
- Method validation or verification records and approvals.
- Calibration certificates and equipment maintenance logs.
- Training and authorization records for technical staff.
- Proficiency testing results and follow-up actions.
- Validation plans with defined acceptance criteria.
Common pitfalls to avoid
- Using unvalidated methods or undocumented deviations.
- Incomplete measurement uncertainty or traceability chains.
- Missing training records for authorized signatories.
- Sampling or chain-of-custody steps not controlled.
- Relying on vendor data without local verification.
Practical checklist
- Confirm methods are validated or verified for intended use.
- Maintain up-to-date equipment and calibration schedules.
- Document staff competence and authorization limits.
- Review PT and QA results before external assessment.
- Confirm acceptance criteria are documented before testing.