Clinical microbiology is a discipline that encompasses a wide range of test methodologies, and it is complex in terms of the organisms and methods used to isolate and identify them. Although significant improvements have been made to the test methods, clinical microbiology remains highly dependent on culture-based methods and phenotypic methods for the identification of culture organisms. The role of clinical microbiology includes the identification and quantification of microorganisms that cause human disease (qualitative and quantitative analysis) and to provide diagnostic information for therapeutic support in the clinical management of patients. The wide variety of pathogens and test methods available make microbiological testing difficult, and therefore detection and correction of errors are important components of quality microbiology laboratory tests.