A quality systems approach for identifying and controlling sources of error with point of care testing devices

Historically, due to the size and nature of the instrumentation, highly skilled laboratory professionals performed clinical testing in centralized laboratories. Today's clinicians demand realtime test data at the point of care. This has led to a new generation of compact, portable instruments permitting "laboratory" testing to be performed at or near the patient's bedside by nonlaboratory workers who are unfamiliar with testing practices. Poorly controlled testing processes leading to poor quality test results are an insidious problem facing point of care testing today. Manufacturers are addressing this issue through instrument design. Providers of clinical test results, regardless of location, working with manufacturers and regulators must create and manage complete test systems that eliminate or minimize sources of error. The National Committee for Clinical Laboratory Standards (NCCLS) in its EP18 guideline, "Quality management for unit-use testing," has developed a quality management system approach specifically for test devices used for point of care testing (POCT). Simply stated, EP18 utilizes a "sources of error" matrix to identify and address potential errors that can impact the test result. The key is the quality systems approach where all stakeholders - professionals, manufacturers and regulators - collaboratively seek ways to manage errors and ensure quality. We illustrate the use of one quality systems approach, EP18, as a means to advance the quality of test results at point of care.