Validation of Analytical Procedures
ICH Q2(R2) sets the validation characteristics to be considered when validating analytical procedures included in regulatory submissions. The R2 revision consolidates the former Q2(R1) text and terminology, broadens applicability to a wider range of techniques including multivariate and spectroscopic methods, and aligns with the development concepts in Q14. It defines specificity/selectivity, accuracy, precision, range, detection and quantitation limits, and their expected demonstration.
What this does not cover
stated in the document's own scope- Does not describe how to develop the procedure — that is ICH Q14
- Does not set the acceptance specification limits — see ICH Q6A/Q6B
- Does not cover bioanalytical method validation — see ICH M10
- Does not mandate a particular statistical software or design
Always verify against the current published text before relying on it for a submission or inspection.
Overview
ICH Q2(R2) specifies the validation characteristics to be considered for analytical procedures submitted in regulatory applications and the way they are demonstrated. It covers specificity/selectivity, accuracy, precision (repeatability and intermediate precision), range, linearity or response, and detection and quantitation limits, applied according to the purpose of the test (identification, impurity testing, or assay). The R2 revision consolidates the prior Q2(R1) text and terminology into a single guideline, broadens applicability to a wider range of analytical technologies including multivariate and spectroscopic procedures, and is aligned with the development guideline ICH Q14.
Legal basis & how it acquires force
Q2(R2) is an ICH guideline implemented by regional adoption (FDA guidance for industry, EU CHMP guideline, and equivalents). It defines how analytical procedures included in a marketing-authorisation application demonstrate fitness for purpose and thereby supports the quality claims relied on under GMP; it replaces the earlier Q2(R1) rather than a statutory predicate rule.
Document structure
| Part | Covers |
|---|---|
| Introduction and scope | Applicability by test type; consolidation of former Q2(R1) |
| Validation characteristics | Specificity/selectivity, accuracy, precision, range, linearity/response, LOD/LOQ |
| Test-type requirements | Which characteristics apply to identification, impurity, and assay procedures |
| Multivariate/technology considerations | Validation of spectroscopic and multivariate procedures |
Key requirements
- Demonstrate specificity/selectivity for the analyte in the presence of expected components
- Establish accuracy and precision (repeatability and intermediate precision) across the range
- Define and justify the validated working range and its linearity/response
- Determine detection limit and quantitation limit where relevant to the procedure
- Provide validation appropriate to the procedure type (identification, impurity, assay)
- Address multivariate and non-traditional analytical procedures where used
- Document validation protocol, acceptance criteria, and results consistent with intended use
Implementation tips
- Match the validation characteristics to the test purpose — an ID test does not need assay-level precision
- Reference Q14 development data to justify ranges rather than re-generating everything at validation
- Update legacy Q2(R1)-era protocols to R2 terminology to avoid mismatch findings at review
- For spectroscopic/multivariate methods, validate the model and its maintenance, not only point results
International alignment
Q2(R2) is harmonised across ICH members and finalised together with ICH Q14. It aligns with Q14 (development) and Q6A/Q6B (specifications) and is implemented regionally by FDA, EMA, PMDA and others.
ICH Q2(R2): frequently asked questions
Quick answers to common questions about ICH Q2(R2).
What changed from Q2(R1) to Q2(R2)?
R2 consolidates the text/terminology, broadens applicability to more technologies including multivariate and spectroscopic methods, and aligns with Q14.
Which validation characteristics apply to an identification test?
Primarily specificity/selectivity; full accuracy and precision characterisation is generally not required for identification.
Does Q2(R2) cover bioanalytical assays?
No. Bioanalytical method validation is governed by ICH M10.