An Overview of Quality Control, Quality Assurance and Quality Management in Clinical Biochemistry Laboratory

A clinical laboratory is engaged in sampling and testing of patient’s samples. The quality of a clinical biochemistry laboratory can be described by its accuracy and reliability of analytical outcomes and time bound delivery of result report. The output of the delivery system in healthcare management rests on the success of quality control and standards of laboratory testing and reporting. The system of regular assessment and monitoring of quality had gradually enhanced clinical care over the time. Clinical biochemical laboratories have made considerable progress in addressing the needs of quality control, to make a difference in patient care by giving reliable results. Quality control (QC) of clinical laboratory is a control sample testing process that is statistically validated to scrutinize and assess analytical procedures applied to obtain the test values of a patient’s specimen for clinical interpretation. A system of QC database, created by performing routine testing of quality control samples, enables to draw QC statistics for the tests conducted in the clinical laboratory. The QC of laboratories had travelled a long distance from “Shewhart cycle” to six sigma quality management system. The clinical biochemistry laboratory has grown from strength to strength in managing, conducting and reporting clinical diagnostic tests. QC ensures that the testing protocol is under control and the test results are reliable and meet the required quality standards as specified by the regulatory authority. The purity and truthfulness of control samples for QC are not only required for proficiency testing but also of prime importance for managing the overall quality. Though QC can be assessed by Westgard’s quality-control selection grids but a chart akin to the method decision chart namely, Operating Specifications (OPSpecs chart) may be of more use and choice. Westgard’s quality-control microcomputer program is amenable to automation. The quality assessment is further strengthened by devising a new graphical tool, the sigma quality assessment chart, for establishing the quality standards of recent testing procedures on a sigma scale. A relatively easy way of assessing the authenticity and imprecision is to compare the within and between laboratories means and standard deviations provided that different laboratories are employing the same instruments and procedures for analyses. The overall quality assessment of the clinical biochemistry laboratory has evolved, wherein internal quality control has been the core of QC that is reinforced by integral external quality assessment. The point of care testing, that is mostly fully automated, is not untouched of QC and require equally stringent QC measures to control the system of checks and balances without increasing much to the cost and affecting the system of maintenance of instruments.