Psychometric Properties of Assessment Tools

Clinicians and researchers are encouraged to acquire competence to analyze the psychometric properties of assessment tools. The importance of appropriate assessment is demonstrated by the increasing number of studies devoted to identifying the best criteria to choose and apply, despite conducting an appropriate evaluation remains a difficult task. Indeed, many instruments have been poorly or incompletely validated over time, thus limiting their use for specific diseases or among populations and countries. Hence, a correct way of assessment aims at replacing an empirical approach with a scientific methodology. This chapter summarizes the core psychometric properties of measurement instruments in the medical field, such as reliability, validity, responsiveness, and interpretability issues. Despite encouraging results and ongoing processes frequently described and claimed in the literature, improving steadily the quality of assessment still constitutes an important challenge. Therefore, better assessment is advised to lead to better treatments, better communication among carers, better evaluation of interventions efficacy, better clinical research, and better understanding of patients’ needs and expectations.