Outcome Measures in PRM: State-of-the-art and Current Perspectives

There is a growing trend to apply Rasch Analysis (RA) to facilitate the development and validation of outcome measures. RA (named after the Danish mathematician Georg Rasch) is an original item-response theory analysis based on latent-trait modeling. The “trait“ here is the variable to be measured, which could be a hypothetical construct, domain, ability or other. It is „latent“ since it cannot be measured directly but is „hidden“ within the person, who may manifest the trait through a set of behaviours assessed by a series of questions (items). The probabilistic Rasch model prescribes how data should be, and wh…