PQ and UAT

When an organization tries to unite facility, utility and equipment qualification principles of IQ, OQ, PQ to a GAMP5 driven approach for computer system validation there is often a bit of confusion about the difference between PQ and UAT. This is aggravated by the outdated IQ,OQ, and PQ that is still required by Annex 15. Add to that the fact everything is computerized these days and we get a lot of confusion.

Difference Between PQ and UAT

Performance Qualification (PQ) and User Acceptance Testing (UAT) are both crucial stages in the software validation process, but they serve different purposes and are conducted at different stages of the software development lifecycle. Here’s a detailed comparison:

Aspect	Performance Qualification (PQ)	User Acceptance Testing (UAT)
Purpose	Verifies that the system performs as expected under real-world conditions.	Confirms that the system meets the user’s needs and requirements.
Scope	Tests the system against the Functional Specification (FS).	Tests the system against the User Requirement Specification (URS).
Conducted By	Usually performed by the system developer or vendor.	Performed by the end users or their representatives.
Focus	Ensures that the system performs consistently under normal and stress conditions.	Ensures that the system provides the required functionality and usability.
Environment	Conducted in an environment that simulates the actual operational conditions.	Conducted in a controlled environment that closely resembles the production environment.
Test Basis	Based on internal processes and procedures, reflecting day-to-day or end-to-end use of the system.	Based on real or hypothetical operations to check usability and functionality.
Outcome	Provides documented evidence that the system is fit for its intended use and complies with regulations.	Provides feedback on whether the system meets user expectations and requirements.
Timing	Typically the final stage before the system is released for production use.	Conducted after the system has passed quality assurance and before final deployment.
Documentation	Test scripts derived from the Functional Specification and internal processes.	Test cases derived from the User Requirement Specification.
Regulatory Compliance	Often required to comply with regulatory standards such as 21 CFR Part 11.	Focuses on meeting the business and user requirements rather than regulatory compliance.

Key Points

• Performance Qualification (PQ):
• PQ tests are designed to verify that the system performs as expected under real-world conditions, ensuring it can handle normal and stress scenarios effectively.
• It is typically conducted by the system developers or vendors and focuses on the system’s performance against the Functional Specification (FS).
• PQ is essential for ensuring that the system is ready for production use and meets all regulatory requirements.
• User Acceptance Testing (UAT):
• UAT is aimed at verifying that the system meets the user’s needs and requirements, ensuring it provides the expected functionality and usability.
• This testing is performed by end users or their representatives and is based on the User Requirement Specification (URS).
• UAT is usually the final validation step before the software is deployed, focusing on user satisfaction and business needs.

Both PQ and UAT are integral to the software validation process, ensuring that system is both technically sound and meet user expectations. While PQ focuses on performance and regulatory compliance, UAT emphasizes user satisfaction and functional correctness.

In an upcoming post I’m going to discuss apply the needs behind these concepts within a ASTM E2500 driven approach that looks at the entire FUSE and Product validation.