The availability of precise, objective and analytical assessment tools is a fundamental factor for the future of Rehabilitation Medicine, in order to document and monitor the effectiveness of physiotherapy/rehabilitation interventions, to set up research protocols and identify prognostic indices. The choice of outcome measures and corresponding measurement scales is a complex process influenced by the interaction between different figures/factors and it requires knowledge of the psychometric and technical requirements of each measurement system. For this issue of EB Talk, we asked Stefano Filippo Castiglia for an in-depth analysis on this topic.