The current version of the metRology for Microsoft Excel add-in focuses on uncertainty analysis using the methods outlined in the JCGM Guide the Expression of Uncertainty in Measurement (often referred to as the GUM). These methods for uncertainty analysis are widely accepted and their use is recommended by many different organizations, including the eight sponsoring organizations of the JCGM, the International Bureau of Weights and Measures (BIPM), the International Electrotechnical Commission (IEC), the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), the International Laboratory Accreditation Cooperation (ILAC), the International Organization for Standardization (ISO), the International Union of Pure and Applied Physics (IUPAP), the International Union of Pure and Applied Chemistry (IUPAC), and the International Organization of Legal Metrology (OIML).
In addition to allowing the user to easily carry out uncertainty computations for a wide variety of different measurement methods, the metRology for Microsoft Excel add-in includes a check on the statistical validity of the results computed via Monte Carlo simulation. The simulation assesses the performance of the GUM uncertainty intervals by computing their approximate attained confidence level averaging over any sources of uncertainty evaluated using Type B methods (i.e. sources of uncertainty evaluated using methods other than statistical analysis).