IFCC recommendations for internal quality control practice: a missed opportunity.

The IFCC Task Force on Global Lab Quality (TF-GLQ) has recently released a new guidance for internal quality control (IQC) practice through an approach translating the general principles as stated in the ISO 15189:2022 standard to a series of practical recommendations. The paper contains however important inaccuracies and shortcomings that, in our opinion, make it a missed opportunity for providing a updated guidance for laboratory professionals. In particular, four important issues are discussed: a) how to design IQC strategies in the traceability era, b) how to define IQC acceptance limits, c) how to estimate measurement uncertainty using IQC data, and d) how to manage comparability between the results provided by different analyzers in the same laboratory. Our analysis underscores the necessity for a more systematic, updated, and evidence-based approach to produce an IQC recommendation in line with the IFCC tradition.