Introduction to Standard Method Performance Requirements Standard Method Performance Requirements (SMPRs®) are a unique and novel concept for the analytical methods community. SMPRs are voluntary consensus standards, developed by stakeholders, that prescribe the minimum analytical performance requirements for classes of analytical methods. In the past, analytical methods were evaluated and the results compared to a “gold standard” method, or if a gold standard method did not exist, then reviewers would decide retrospectively if the analytical performance was acceptable. Frequently, method developers concentrated on the process of evaluating the performance parameters of a method, and rarely set acceptance criteria. However, as the Eurachem Guide points out: “ . . . the judgment of method suitability for its intended use is equally important . . .” (1) to the evaluation process. International Voluntary Consensus Standards An SMPR is a form of an international, voluntary consensus standard. A standard is an agreed, repeatable way of doing something that is published as document that contains a technical specification or other precise criteria designed to be used consistently as a rule, guideline, or definition. SMPRs are a consensus standards developed by stakeholders in a very controlled process that ensures that users, research organizations, government departments, and consumers work together to create a standard that meets the demands of the analytical community and technology. SMPRs are also voluntary standards. AOAC cannot, and does not, impose the use of SMPRs. Users are free to use SMPRs as they see fit. AOAC is very careful to include participants from as many regions of the world as possible so that SMPRs are accepted as international standards. Guidance for Standard Method Performance Requirements Commonly known as the “SMPR Guidelines.” The first version of the SMPR Guidelines were drafted in 2010 in response to the increasing use and popularity of SMPRs as a vehicle to describe
the analytical requirements of a method. Several early “acceptance criteria” documents were prepared for publication in late 2009, but the format of the acceptance criteria documents diverged significantly from one another in basic format. AOAC realized that a guidance document was needed to promote uniformity. An early version of the SMPR Guidelines were used for a project to define the analytical requirements for endocrine disruptors in potable water. The guidelines proved to be extremely useful in guiding the work of the experts and resulted in uniform SMPRs. Subsequent versions of the SMPR Guidelines were used in the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) project with very positive results. The SMPR Guidelines are published in the Journal of AOAC INTERNATIONAL and Official Methods of Analysis. Users of the guidelines are advised that they are: (1) a guidance document, not a statute that users must conform to; and (2) a “living” document that is regularly updated, so users should check the AOAC website for the latest version before using these guidelines. The SMPR Guidelines are intended to provide basic information for working groups assigned to prepare SMPRs. The guidelines consist of the standard format of an SMPR, followed by a series of informative tables and annexes. SMPR Format The general format for an SMPR is provided in Annex A. Each SMPR is identified by a unique SMPR number consisting of the year followed by a sequential identification number (YYYY.XXX). An SMPR number is assigned when the standard is approved. By convention, the SMPR number indicates the year a standard is approved (as opposed to the year the standard is initiated). For example, SMPR 2010.003 indicates the third SMPR adopted in 2010. The SMPR number is followed by a method name that must include the analyte(s), matrix(es), and analytical technique (unless the SMPR is truly intended to be independent of the analytical technology). The method name may also refer to a “common” name (e.g., “Kjeldahl” method). The SMPR number and method name are followed by the name of the stakeholder panel or expert review panel that approved the SMPR, and the approval and effective dates. Information about method requirements is itemized into nine categories: (1) intended use; (2) applicability; (3) analytical technique; (4) definitions; (5) method performance requirements; (6) system suitability; (7) reference materials; (8) validation guidance; and (9) maximum time-to-determination. An SMPR for qualitative and/or identification methods may include up to three additional annexes: (1) inclusivity/selectivity panel; (2) exclusivity/cross-reactivity panel; and (3) environmental material panels. These annexes not required. Informative tables.—The SMPR Guidelines contain seven informative tables that represent the distilled knowledge of many years of method evaluation, and are intended as guidance for SMPR working groups. The inf