[Evaluation and standardization of radioimmunoassays]

The term "standardization" may be applied to RIA methods to indicate the "definition of quality characteristics" the level of which must be defined on the basis of the evaluation of the "analytical procedure/specific reagents" system. Each laboratory, by applying a suitable long-term quality control system, must assure the consistent maintenance of the "standardization status" established for all mehtods it uses. As a matter of fact, in the case of RIA, materials are used that have a limited stability, that cannot be produced in large quantities, and that possess a complex composition not always well defined chemically. However, a remarkable role in the standardization process belongs to the producers of special reagents intended for RIA. In order to help the standardization of RIA methods, some programs of inter-laborator cooperation have been worked out in recent years. Among them mention is specifically made of three studies regarding the dosage of insulin: the most recent of them is devised and coordinated by the Instituto Superiore di Santià in cooperation with the Laboratory of Clinical Physiology of the National Research Council of Pisa. The availability of standardized materials is estremely important: for antigens, some materials are already in existence, but it is desirable that the various manufacturers shall follow more uniform criteria in their standardization. As far as the application of the RIA methods in the diagnostic field is concerned, the need exists for the use of standardized basic schemes that would include and unambiguously express all the useful information available in order to define better the clinical significance of the analytical data obtained.