Definition and Validation of the ICF – Usability Scale

Usability assessment is an important issue of the development of products and services based on information technologies. Questionnaires and scales are valuable instruments to collect large amounts of subjective data from users and their application is a reliable technique to assess usability. Furthermore, when considering products and services for older adults, the International Classification of Functioning, Disability and Health (ICF) might be used as a conceptual model for usability assessment.This paper presents the development and validation of the ICF-Usability Scale (ICF-US), an instrument supported by concepts and terminologies related to ICF and that is part of a comprehensive framework for the design, development and evaluation of ambient assisted living products and services for older adults.The methodology that has been followed in the study reported by this paper comprises two phases: the development and the validation phases. The last phase consisted in an observational study performed in a nursing home involving 32 adults and its results suggest acceptable reliability and validity values for the ICF-US.