Reporting results with (Un)certainty

Background A degree of uncertainty occurs with every measured laboratory result due to both analytical and biological variation. The tools of Total Observed error (TE O ) and dispersion based on biological variation have helped veterinary labs quantify the causes of variation that lead to measurement uncertainty (MU). International organizations recommend that the amount of MU in veterinary laboratory results be identified and communicated. The expanded measurement uncertainty (EMU), dispersion, and reporting interval adjustment have been recommended as tools to allow communication of MU to laboratory data users but are not commonly discussed in the veterinary literature. Objective Using the vocabulary of Total Observed error and biological variation and examples from veterinary medicine, a review of the theory and application of the EMU, dispersion, and the methods for deriving an appropriate reporting interval recommended by Hawkins and Badrick, is presented. Conclusions By addressing the way that MU is communicated to users of laboratory results, the laboratory enables users to better understand the potential uncertainty associated with reported results, helps to prevent over and under‐interpretation of data, and improves diagnostic accuracy and patient care.