Electronic quality control, the total testing process, and the total quality control system

Traditional statistical quality control (QC) using matrix controls is often difficult to implement in point-of-care settings. Alternative QC procedures, such as electronic QC, have been developed by many manufacturers and approved for use by regulatory and accreditation organizations. Electronic QC usually involves the substitution of an electrical signal for the signal that would normally be generated by a sensor responding to an analyte in a specimen; sometimes an artificial nonliquid sample is substituted to cause the sensor to generate an electrical signal. The usefulness of electronic QC can be assessed by identifying the steps in the total testing process that are being monitored. An example is provided for blood gas measurements to illustrate the steps that can be monitored by different types of QC procedures and materials. The need to monitor all of the steps generally requires a combination of procedures and materials, or a total QC system that includes electronic QC, matrix controls, and even real patient specimens. Electronic QC is an essential part of the total QC system, but is not by itself sufficient.