In a clinical laboratory, verification and validation are critical for ensuring the accuracy, reliability and compliance of diagnostic tests—and ultimately for ensuring patient safety. While the terms are sometimes used interchangeably, they have distinct meanings. Knowing the difference will save your lab time and effort, as well as lower compliance risks. 

ISO 15189 is now mandated by the IVDR for most labs performing in-house tests, and it is this ISO that lays out quality and competence requirements for medical labs—including verification and validation. IVDR also has specific performance evaluation requirements for validating in-house tests, as does the recent global ISO 5649 for lab-developed tests.  

Here’s what you need to understand about these two terms and when to perform them.  

Verification: Confirming Performance 

• What it is: The process of confirming that a test method (typically a commercial IVD device) performs as expected in your lab’s specific setting. 

• When it’s needed: When a lab adopts a commercial device, such as a CE-marked (or in the U.S. an FDA-cleared) assay, reagent or instrument. 

• Purpose: Ensures that use of the test in the lab environment – with its equipment, personnel, and sample types— is accurate and safe for patient diagnosis and meets the manufacturer’s performance claims. 

• Example: A lab purchasing a CE-marked PCR assay for infectious disease testing must verify that it yields the expected accuracy, precision, and sensitivity in their facility before using it for patient diagnosis. 

Validation: Establishing Performance 

• What it is: A more extensive process that demonstrates and documents that a new or modified test method is appropriate to its intended purpose and performs with an acceptable level of accuracy. 

• When it’s needed in the lab: When a lab develops an in-house test or modifies a commercial product, both ISO 15189 and IVDR performance evaluation requirements mandate validation. 

• Purpose: Ensures that the test delivers accurate, reliable, and clinically meaningful results that align with its intended purpose. 

• Example: A lab developing an in-house next-generation sequencing (NGS) test for oncology must validate it for the stated intended purpose and by assessing parameters such as sensitivity, specificity, reproducibility and clinical performance before using it for patient diagnosis. 

Key Differences in the Laboratory Setting 

Feature	Verification	Validation
Scope	Confirming performance	Establishing performance
When needed	Commercial IVD tests newly introduced to a lab Existing tests following a change at the lab (maintenance, a new software system, etc)	Lab-developed or modified tests
Regulatory requirement	Required for CE-IVD tests under ISO 15189 Defined by the device manufacturer in the Instruction for Use	Mandatory for in-house tests under IVDR and according to ISO 15189
Complexity	Less extensive	More extensive
Example	When switching from one CE-marked genetic analysis device to a new device from the same or a different manufacturer	Off-label use or repurposing of a CE device – e.g., for a new specimen type, target population, etc.

Verification and Validation Process for In-House Tests 

When a lab modifies a commercial IVD test to meet patient needs, both verification and validation must be carried out: 

1. A lab first verifies the manufacturer’s performance claims for the device are reproduceable in their lab. 

2. If modifications are made (e.g., using a test for a different patient population or with a different sample type), the lab must then validate the modified version as an in-house test. 

In other words, in-house tests require full validation – but prior to this the lab must first confirm via verification that any commercial device used in the test performs in their lab according to the manufacturer’s original claims.  

Verification guidelines can be found in ISO 15189. Validation guidelines are also included in ISO 15189, but EU labs also need to ensure that IVDR Annex I, Section 9 performance evaluation requirements have been met and documented where applicable. 

The bottom line 

Verification and validation are essential for ensuring that results in your lab are accurate, reliable, clinically useful and thus safe for patients. They are also integral to meeting the regulatory requirements of ISO 15189, IVDR, CLSI or CLIA in the U.S. 

Platomics’ digital solutions make lab compliance easier. 

*We have compiled the above information to the best of our knowledge, yet our blog entries do not constitute expert advice and cannot substitute your own examination of the legal situation applicable to you and your institution.