Pre-analytical phase in clinical chemistry laboratory

The laboratory testing process is divided into the pre-analytical, analytical and post-analytical phases. For obtaining reliable test results, the prevention and detection of errors at all steps is required. While analytical standards have been developed by recognized quality control criteria, there is a scarcity in the development of standards for the preanalytical phase. This phase is most prone to errors as the steps involved are directly dependent on humans and are out of direct control of the laboratory. Such errors in preanalytical stage often only become apparent in the analytical or post-analytical phase. The development of a pre-analytical quality manual is essential in achieving total quality control. Correct practices and strategies of error prevention can reduce preanalytical errors. This review focuses on prevention of pre-analytical errors that occur while collecting a specimen of blood, urine and cerebrospinal fluid. Most of these can be easily prevented with understanding and education of the personnel involved in and responsible for executing this crucial pre-analytical phase.