ISO/TR 21074:2016 describes how to determine the repeatability and reproducibility of precision tests performed within standardization work using the chemical analysis method. Specifically, this document explains the procedure for calculating precision, using precision test data of ISO 57253:1994, Table D.2 for the precision test in ISO 9647:1989 as an example.
The procedure of the international test for determining precision is described in ISO 57252 and ISO 57253.