The running of standards in clinical chemistry and the use of the control chart.

The progress of clinical medicine has been considerably aided in the past few decades by the increased number of laboratory tests available and the improvement in their specificity and accuracy. Nevertheless, the reliability of analytical results from clinical laboratories has been questioned by many individuals, and several independent surveys have more than justified the suspicion (Belk and Sunderman, 1947; Shuey and Cebel, 1949). In these surveys blame has been placed on poor supervision of personnel, poorly trained and insufficient personnel, poor equipment, poor choice of methods available, and so on. The vast majority of clinical chemical analyses are and probably will continue to be performed by, and supervised by, people not trained as chemists. In such cases laboratory staff follow methods in the so-called "cook-book" fashion with only sparse knowledge of the chemistry involved. Faced with this problem, it becomes the job of the clinical chemist to outline procedures in detail so as to make them as fool-proof as possible. It is the purpose of this paper to discuss the importance of running routine standards with clinical chemical analyses, the types of standards that can be employed, and the treatment of the data accumulated so as to give reasonable assurance that the results being obtained are within a known permissible error. By such means the laboratory can strengthen the reliability of its results and the faith of the physician in them.