Validation of Reagents and Equipment
This domain tests whether a laboratory can demonstrate, with records, that a method, reagent lot or instrument is fit for its intended use. Distinguish validation, which establishes performance for a new method, from verification, which confirms that a method already validated elsewhere meets stated performance in your laboratory. Calibration establishes the relationship between signal and concentration; verification confirms that a claimed performance is met.
Qualification and method checks
Equipment qualification commonly follows installation, operational and performance stages. Reagent and lot checks may include appearance, expiry, storage, package integrity and manufacturer instructions, plus laboratory-defined acceptance testing. Method verification covers precision, trueness or bias, analytical range, limit of detection or quantification where relevant, interference and reference interval suitability. Keep raw data, acceptance criteria, reviewer sign-off and deviation records.
Worked example
A laboratory receives a new lot of a rapid HIV test. The method is already validated and in routine use, so full validation is not automatically required. The laboratory should perform its documented lot-to-lot verification against the manufacturer's instructions and local policy, using known reactive and non-reactive samples, checking storage and expiry, and recording acceptance before releasing the lot. If performance fails, quarantine the lot and investigate.
Traps
- Calling every check validation when the task is verification.
- Assuming a manufacturer's claim removes the need for local verification.
- Using only easy or known-negative samples.
- Failing to define acceptance criteria before testing.
- Omitting equipment temperature, calibration and maintenance records.
- Releasing a new lot before documented approval.