Expert Opinion on Verification of Antimicrobial Susceptibility Tests

How to verify and validate a clinical microbiology test before it can be used in routine diagnostics: a practical guide

BACKGROUND

Before a new test can be routinely used in your laboratory, its reliability must be established in the laboratory where it will be used. International standards demand validation and verification procedures for new tests. The International Organization for Standardization (ISO) 15189 was recently updated, and the European Commission's In Vitro Diagnostic Regulation (IVDR) came into effect. These events will likely increase the need for validation and verification procedures.

OBJECTIVES

This paper aims to provide practical guidance in validating or verifying microbiology tests, including antimicrobial susceptibility tests in a clinical microbiology laboratory.

SOURCES

It summarizes and interprets certain parts of standards such as ISO 15189:2022, and regulations, such as IVDR 2017/746 regarding validation or verification of a new test in a routine clinical microbiology laboratory.

CONTENT

The reasons for choosing a new test and the outline of the validation and verification plan are discussed. Furthermore, the following topics are touched upon: the choice of reference standard, number of samples, testing procedures, how to solve the discrepancies between results from new test and reference standard, and acceptance criteria. Arguments for selecting certain parameters (such as reference standard and sample size) and examples are given.

IMPLICATIONS

With the expected increase in validation and verification procedures because of the implementation of IVDR, this paper may aid in planning and executing these procedures.