
Accuracy
Accuracy can be defined as a measure of the difference between the "true value" and a set of experimentally determined data, and is affected by both systematic error (bias) and random error (precision).
Bias
Error systematically occurring during the analysis. Bias can result from a lack of calibration, is constant within a method and thus should be predictable. (Click
for diagram - 7KB).
Precision
Precision relates to the spread of experimentally determined data. The smaller the data variation, the greater the precision of the analytical method.
Repeatability
Repeatability is the standard deviation of a series of quantitative measurements performed with the same method and sample under similar conditions (e.g. instrument, analyst, etc) over a short period of time.
Reproducibility
Reproducibility is the standard deviation of a series of quantitative measurements performed with the same method and sample under different conditions (e.g. different instrument, analyst, laboratory etc) over a long period of time.
Robustness
Robustness, also called ruggedness, is the measure of a method�s capacity to remain unaffected by small variations in the main parameters.
Range
The range is the interval between the lower (limit of detection {LoD} or limit of quantitation {LoQ}) and upper concentration of an analyte, for which the analytical method was proved to be suitable. (Click
for diagram - 11KB)