Within the health system there are two different models for assessing the construct “functioning/disability”: the “activities of daily living (ADL)” approach (or Katz/Barthel model), and the “Functioning” (ICF) approach developed by WHO. The ICF was developed to provide a more comprehensive framework, based on the view of a health condition or disease as the interaction of body function and structures, activities and participation, which are in turn impacted on by social and environmental factors. The importance of participation as an outcome is also highlighted (WHO, 2001).