Review of the new edition of ISO 13528

The international standard ISO 13528 is an important reference document for proficiency testing providers and testing laboratories alike, which provides guidance on the use of statistical methods in proficiency testing. With a view to bringing the document in harmony with the ISO/IEC 17043:2010, the first edition of ISO 13528 was revised and the new edition was published in September 2015. This paper attempted to review and discuss the major changes introduced in the new edition of ISO 13528, particularly the part on statistical design with respect to the objective of proficiency testing scheme and the considerations on assigned value determination and performance scoring. Moreover, procedures provided in the new edition of ISO 13528 for qualitative proficiency testing schemes and various robust statistical methods would also be briefly discussed in the paper.