intralaboratory comparison 

https://doi.org/10.1351/goldbook.08083
Organization, performance, and evaluation of measurements or tests on the same or similar items within the same laboratory in accordance with predetermined conditions.
Source:
PAC, 2021, 93, 997. 'Metrological and quality concepts in analytical chemistry (IUPAC Recommendations 2021)' on page 1029 (https://doi.org/10.1515/pac-2019-0819)