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Glossary Term
The international quality-management standard for medical device manufacturing. Certification does not certify individual products, but suppliers with ISO 13485-registered production generally support tender documentation more reliably.
Glossary Term
A method for converting an individual score into a standard form. While similar to a z-score, t-score is used when the conversion is made without knowledge of the population standard deviation and mean.
Glossary Term
A method for converting an individual score into a standard form. The z-score indicates how far and in what direction an item deviates from its distribution's mean, expressed in units of standard deviation. Calculation of a z-score requires knowledge about the population's standard deviation and mean.
Glossary Term
A storage facility of biospecimens that includes tissue samples, fluids, and molecular derivatives such as DNA, RNA, and proteins. The biorepository has stringent guidelines regarding the standardized collection, handling, storage, and documentation of biological specimens.
Glossary Term
The act of checking or adjusting (by comparison with a standard) the accuracy of a measuring instrument.
Glossary Term
An instrument designed to measure the size of an opening or one used to increase the diameter of an opening; can also refer to a standard or reference material used to set the operating parameters of an instrument.
Glossary Term
The ratio of standard deviation to mean, expressed as a percentage or fraction.
Glossary Term
The probability that a test will produce a true negative result when used on non-effected subjects as compared to a reference or "gold standard". The specificity of a test can be determined by calculating: number of true negative results divided by the sum of true negative results plus number of false positive results.
Glossary Term
A PCR format that partitions each sample into thousands of sub-reactions and calls each partition positive or negative, giving absolute quantification without a standard curve. Useful for low-level targets, copy-number work, and reference material characterization; throughput and per-test cost differ from qPCR.
Glossary Term
A family of probability density functions whose mean, median and mode are identical. The function generates a symmetrical curve, whose position and shape is determined by its location and scale parameters, the mean and standard deviation respectively. The standard normal distribution has a location parameter of 0 and a scale parameter of 1.
Glossary Term
How close amplification is to ideal doubling each cycle, reported as a percentage or derived from the standard curve slope. Efficiency near 90–110% with a linear standard curve supports quantification claims; it is a standard checklist item when auditing assay validation dossiers.
Glossary Term
A measure of the correlation of two variables X and Y measured on the same object or organism, that is, a measure of the tendency of the variables to increase or decrease together. It is defined as the sum of the products of the standard scores of the two measures divided by the degrees of freedom.
