The Science of Quality Control in the Laboratory
In a broader sense, quality control is a means to ensure that the product quality remains the same or improves. It denotes the construction of control protocols to standardize production processes to achieve consistent quality outputs.
The laboratory's quality control seeks to streamline lab processes and set control measures to detect and rectify discrepancies. The end goal is to minimize errors, which consequently ensures improved results quality.
In that regard, quality control is a measure of precision. It determines how consistent a system is in producing accurate results under varying conditions.
Quality control processes in a laboratory are often conducted at the beginning of every shift as staff interchange. It is also essential to run quality checks after equipment undergoes service or calibration before putting it back into service. This helps determine accurate results before entrusting the equipment to patient use.
Detailed analysis can help determine how close output is to an expected value. The precision value determines how consistently the instrument can reproduce the same value, for the same test sample, under the same test conditions.
Quality control and quality assurance are both part of quality management. However, they differ in purpose and application. Quality assurance puts in place mechanisms and systems to instill confidence in management and stakeholders that the output will fulfill all requirements. However, quality control has to do more with inspection, to determine compliance with quality requirements.
A few elements are mandatory for an excellent quality control system. The system must be easy to use and reproduce over many groups of control samples. It must also have minimal vial-to-vial variations. If not, these discrepancies will appear as systemic errors arising from the measurement system. Moreover, its stability should be dependable for extended periods and not susceptible to interferences in the short term.