OBJECTIVE To offer methods for proficiency testing providers to correctly apply the performance statistics that includes assigned value and standard deviations from participant results, thereby ensuring the validity of proficiency evaluation conclusions.

METHODS To mitigate the potential adverse effects of the inherent limitations of the "use of participant results to determine statistical measures" method on competency assessment outcomes, this study systematically reviewed the technical requirements outlined in the guidelines issued by the International Organization for Standardization, the accreditation criteria and guidance documents released by the China National Accreditation Service for Conformity Assessment, the national standards of the People's Republic of China promulgated by relevant departments, and the metrological technical specifications. It provided an expanded introduction and in-depth interpretation of the statistical knowledge involved. A comprehensive analysis was conducted, focusing on key aspects such as data review, commonly available statistical methods and their application conditions, and the performance metrics of various statistical algorithms.

RESULTS The advantages and disadvantages of the determination of criteria for evaluation of performance from data obtained in the same round of a proficiency testing scheme were summarized.

CONCLUSION This study illustrates the fundamental principle that "no statistical method is universally perfect for all scenarios" through concrete examples, thereby reminding proficiency testing providers to place high importance on the proper selection and application of statistical methods during operational planning.