PROPOSAL for the distribution of a certified standard for use in hemoglobinometry.

HERE IS PROBABLY NO PROCEDURE more commonly used in clinical laboratories than hemoglobinometry and few that are less satisfactory in their results. The deficiencies may reside, in part, in inadequacies of the chosen method. In larger part, however, they result from manipulative errors in the measurement and processing of the samples of blood. The latter involve questions of technical proficiency which are entirely within the control of the analyst himself. When, however, he converts his observations-gasometric or photometric readings, measurements of specific gravity, etc.-to grams of hemoglobin in 100 ml. of blood, he must depend upon his own calibration or a calibration supplied by an instrument maker, 1)0th procedures involving a conversion factor taken from the literature. To be satisfied that the calibration remains valid for the instrument, reagents, and technical routines in use in his laboratory, he should periodically undertake a precise and time-consuming series of standardizations. If a uniform hemoglobin standard were available nationally and a single method of analysis widely practiced, the individual laboratory would then have assurance not only that its results would be comparable from month to month, but that they would also be comparable with those from other laboratories employing the same standard. Inconsistencies in results that persisted under these conditions could then be clearly attributed to technical and maiiipulative errors.