Improvement in the quality of enzyme determinations by Scandinavian laboratories upon introduction of Scandinavian recommended methods.

The last annual Scandinavian proficiency survey (January 1975) offered an opportunity to evaluate the effect of the introduction of recommended methods for ASAT, ALAT, LD, and ALP on routinely performed enzyme determinations in clinical chemical laboratories. The results obtained by the recommended methods showed a marked improvement in precision, bringing the interlaboratory variations down to levels that have previously been achieved only for the determination of non-enzymic constituents. Enzymes for which no recommended method have been proposed were still determined with low interlaboratory precision.