IFCC recommendation: The theory of reference values. Part 4. Control of analytical variation in the production, transfer and application of reference values

This paper is the fourth in a series of Recommendations on the Theory of Reference Values. The others cover:Part 1. The Concept of Reference Values 1.Part 2. Selection of Individuals for the Production of Reference Values 2.Part 3. Preparation of Individuals and Collection of Specimens for the Production of Reference Values 3.Part 5. Statistical Treatment of Collected Reference Values. Determination of Reference Limits 4.Part 6. Presentation of Observed Values Related to Reference Values 5.A Guide to the Documents is currently in preparation.The Expert Panel of Theory of Reference Values (EPTRV) was created in 1970 by the Committee on Standards (at present: Scientific Division) of the International Federation of Clinical Chemistry (IFCC). Its task was to develop a nomenclature and recommend procedures for the production of reference values and their treatment, and presentation of observed values in relation to reference data.The first document in the above-mentioned series describes the subject of reference values and defines various terms. It would be best to read it for a thorough understanding of the present document.