### The estimate of measurement uncertainty

The estimate of measurement uncertainty is important in Laboratory Medicine because it is required for reference measurement laboratories to obtain/maintain the accreditation according to ISO 17025:2003 and ISO 15195:2005 and for clinical laboratories to obtain the accreditation according to ISO 15189:2012. There are two approaches to estimate measurement uncertainty, the so-called ‘bottom-up’ and ‘top-down’ approaches.