Cooperative Survey of "SMA" Analyzers in Wisconsin—A Method of Improving Interlaboratory Performance
Abstract A state-wide cooperative quality-control program for automated multichannel analytical systems is described. The survey benefits participating laboratories by providing, through regular comparison, a means of improving interlaboratory precision. A common lot of reference material used for a large group of similar multichannel analyzers is shown to significantly improve their precision. The study delineates components of interlaboratory variation resulting from the inconsistency of the reference materials and from the inherent precision of the analyzers. Errors in the assay values of commercial controls and reference sera, as well as problems of homogeneity in these products, are documented. These errors make some form of regular interlaboratory comparison an essential element of a total quality-control program
