Delta check system for detection and further management of laboratory errors. First report. Graphical presentation of results.

The delta check system is effective for detecting errors that may occur during the whole course of tests, from the time a laboratory test is ordered until it is interpreted. This system detects errors that exceed the preestablished values by comparing present data with the most adjacent ones in all items for each case. Graphical presentation of delta-checked data led to easier judgment as to whether such a difference is due to erroneous testing or changes in the patient's condition on the basis of whether a difference in values is limited to a particular item or is common to pathologically associated multiple ones. Furthermore, since test items were classified by analytical instruments, it became easier for us to determine at which process of the testing an error occurred. This report gives the present status of utilization of delta check system in our laboratory.