Accreditation |
Third-party statement based on a decision following review that competence to carry out a task has been demonstrated. |
Accuracy |
Closeness of agreement between a single test result or measurement result and the true value. |
Analyte |
Any substance whose identity or concentration is to be determined. |
Bias |
The difference between the mean value of a set of test results or measurement results and the true value. |
Calibration |
Operation that establishes the relation, obtained by reference to one or more measurement standards, between the response of an instrument and the values of the standards. |
Certification |
Third-party statement based on a decision following review that fulfilment of specified requirements have been demonstrated. Usually related to products, processes, systems or persons. |
Certified reference material (CRM) |
A reference material characterized by a metrologically valid procedure for one or more specified properties, accompanied by a certificate that states the value of the specified property, its associated uncertainty, and a statement of metrological traceability. |
Control charts |
Routine charting of data obtained from the analysis of quality control materials to check that the results lie within predetermined limits. |
Error |
The difference between a result of a measurement and the true value of the measurand. |
Fitness for purpose |
A formal process of assessing that a method is suitable for a given application. |
Good Laboratory Practice |
A world-wide quality management system for the design, conduct and reporting of studies in support of licensing/ product registration of drugs/food/chemicals for human or veterinary use. Registration to this system is frequently mandatory for work of this nature. |
Limit of detection |
The lowest amount of an analyte that can be measured with reasonable statistical certainty. |
(Sample) Matrix |
All components of the test sample excluding the analyte. |
Measurand |
A particular quantity subject to measurement. |
Measurement uncertainty |
A range of values within which the true value of the measurement is expected to lie with a given level of confidence. |
Precision |
The closeness of agreement between independent test results obtained under stipulated conditions. A precision estimate is a statistical measure of the spread of the results obtained from a series of replicate measurements. |
Proficiency Testing |
Determination of laboratory testing performance by means of interlaboratory comparisons. |
Quality Assurance |
Part of quality management focused on providing confidence that quality requirements will be fulfilled. It is all the activities undertaken by an organisation to ensure a defined standard of quality for its goods or services. |
Quality control |
Part of quality management focused on fulfilling quality requirements. |
Quality control chart |
Routine charting of data obtained from the analysis of quality control materials to check that the results lie within predetermined limits. |
Quality control sample (material) |
A material that is fully characterized in-house or by a third party, similar in composition to the types of samples normally examined, stable, homogeneous and available in large quantities so that it can be used over a long period of time for monitoring method performance.. |
Reference Material |
A Material, sufficiently homogeneous and stable with respect to one or more properties, which has been established to be fit for its intended purpose. |
Standard operating procedure |
A documented set of instructions for an analytical method that completely specifies how to operate the method. It includes a statement of the scope of the method, what apparatus and chemicals are to be used, and how the reported result is to be calculated and expressed. |
Traceability |
A property of the result of a measurement or the value of a standard whereby it can be related to stated references, usually national or international standards, through an unbroken chain of comparisons all having stated uncertainties. |
Trace analysis |
Analysis of samples containing a low concentration of the anlayte(s) of interest – typically less than 100 mg kg-1. Note that trace analysis is also used to describe the analysis of a very small quantity of sample material (especially in forensic analysis). |
Validation |
Confirmation by examination and provision of objective evidence that the particular requirements for a specified intended use are fulfilled. |