Abstract
The recovery method—applied increasingly frequently to studying the effectiveness of analytical procedures—is subjected to a detailed critical appraisal. Two versions of this method that have practical applications are presented, as are broad interpretation possibilities. Effects that may occur during the analytical procedure have been classified and the significance of these effects for the reliability of results gained by the recovery method has been defined. The similarities and differences between this method and the standard addition method have been indicated. Theoretical deliberations are supported by results of analysis of blood samples for selenium and arsenic content by the atomic fluorescence spectrometry method. It has been shown that the “surrogate” version of the recovery method, although potentially attractive from the analytical point of view, in practice can be very unreliable and the more complex the laboratory procedures for preparing the sample for measurement, the more risky is its application.