Imaging: the need for standardization

The five stages in the evolution of a new method or measure are discovery (by design or inadvertent), development, testing, standardization and application. However, measures may be accepted, disseminated and used before they have been formally evaluated and standardized. This chapter describes the properties of measurement in the medical sciences and the process of standardization. It includes an example of the development and standardization of a magnetic resonance imaging rheumatoid arthritis score, and ends with a matrix that can serve as a guide for systematic appraisal and standardization of outcome measures, such as imaging outcomes. Using the matrix, one can determine the gaps in knowledge and what further evaluation is needed in one or more domains or metrics.