ASTM International - ASTM D6259-15(2019)
Standard Practice for Determination of a Pooled Limit of Quantitation for a Test Method
|Publication Date:||1 May 2019|
|ICS Code (Test conditions and procedures in general):||19.020|
significance And Use:
5.1 Background-In a single laboratory, the limit of quantitation, LOQ, equal to ten times the standard deviation obtained under repeatability conditions extrapolated to zero concentration... View More
5.1 Background-In a single laboratory, the limit of quantitation, LOQ, equal to ten times the standard deviation obtained under repeatability conditions extrapolated to zero concentration (s0) based on samples with close to zero concentrations has been recommended.3 A test result at this LOQ has an uncertainty of ±30 % at the 99 % confidence level.
5.1.1 This practice uses a regression technique to determine a similar limit for a test method (PLOQ) using statistically pooled repeatability standard deviations over multiple operators/laboratori
5.1.2 The regression technique described in this practice can also be used to determine a limit of quantitation specific for a single laboratory (LLOQ). The limit thus quantified for one laboratory is defined by this standard as the laboratory limit of quantitation (LLOQ).
5.1.3 It should be noted that since differences in repeatability testing capabilities between different laboratories can exist, therefore, LLOQ determined at a single laboratory can be different than the PLOQ determined for the test method.
5.2 Values below the PLOQ are deemed by this practice to be too uncertain for meaningful use in commerce, or in regulatory activities.View Less
1.1 This practice covers the use of standard regression techniques and data from an interlaboratory study to determine a lower quantitative limit for a test method. This determined lower limit represents the numerical limit at or above which the test results are considered to be quantitatively meaningful for commerce or regulatory activities by this practice. It is defined by this standard as the pooled limit of quantitation (PLOQ) for the test method.
1.2 This practice is applicable to test methods that are capable of producing numerical test results close to zero. Examples are those test methods that determine quantitatively the concentration of analyte(s) near zero.
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.