As medical laboratory tests involving detection of nucleic acids become more common, well-designed and executed proficiency schemes are needed to assure quality and to further the development of this complex and rapidly growing area of laboratory medicine. MM14-A2—Design of Molecular Proficiency Testing/External Quality Assessment; Approved Guideline—Second Edition has been developed to guide the individuals and organizations responsible for providing proficiency testing (PT). It will also serve medical laboratories with a benchmark for evaluation of new programs or to facilitate development of laboratory-based PT or alternative assessment schemes when appropriate schemes are not available from formal programs. Specific sections discuss the design of PT programs; sources of materials; production, manufacture, and QA of samples; sample distribution; receipt and evaluation of data; and reporting responsibilities. Also discussed are examples of method-based PT programs and alternative assessment strategies and how they can be used to evaluate laboratory test performance. This document also lists and describes relevant regulatory and guidance documents related to PT.

This document replaces the first edition of the approved guideline, which was published in 2005. Several changes and additions were made in this edition; chief among them is the revision of the sections describing relevant regulatory and guidance documents and the addition of sections describing examples of method-based proficiency testing (PT) programs and alternative assessment strategies. This edition also recognizes and emphasizes the roles and responsibilities of the medical laboratory in providing PT through informal sample exchange programs.

The purpose of this guideline is to complement currently available regulatory and guidance documents regarding the management and operations of proficiency testing/external quality assessment (PT/EQA) programs. Presently, these documents guide the administration of such programs, but consideration of panel selection, analysis of data for evolving technologies and tests with many possible measurands, method-based PT/EQA, and reporting to participants are not addressed. For molecular methods, these issues are important for all stakeholders, including regulatory agencies, accrediting agencies, PT/EQA providers/organizations, PT/EQA materials manufacturers, medical (clinical) laboratories, and test/reagent manufacturers. 

This document addresses both large formal PT/EQA programs as well as medical laboratorians who produce, distribute, and administer PT/EQA schemes, and should provide guidance for the development and implementation of new PT/EQA programs for nucleic acid testing or modifying existing schemes. This guideline does not address the process of testing and reporting PT/EQA in the medical laboratory, medical laboratory inspection, accreditation, or other regulatory processes. 

This guideline focuses on nucleic acid (DNA and RNA) PT in the areas of human genetics, infectious disease, molecular oncology, and pharmacogenetics. Though written specifically to address needs in this area, the principles stated may be applicable to programs outside of nucleic acid testing. Organizations and programs that send blinded samples to laboratories and analyze the submitted results carry several different names. These challenge programs may be called PT/EQA, quality assessment or assurance programs, QC programs, ring trials, sample exchange, and EQA/assurance. Countries or regions may place regulatory distinctions on these names. 

To facilitate the readability of this document, the terms PT/EQA, PT/EQA provider/organization, and PT/EQA program have been chosen to describe such activities, and regulatory categorization is not implied unless specifically noted.