A written test method is subjected to an ILS to evaluate its performance. The ILS produces a set of statistical estimates that depend upon the method, but also are influenced by the laboratories and test materials involved in the study. For that reason, the ILS task group must interpret these estimates, aided by this guide and using analytical judgment, to decide if the method is suitable to be balloted for publication as a standard. The task group may use this guide to help them prepare the precision and bias statements that are a required part of the method.

1.1 This guide covers procedures to help a task group interpret interlaboratory study (ILS) statistics to state precision and accuracy of a test method and make judgments concerning its range of use.

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.