As a multidimensional concept, the term active ageing includes concepts of activity, health, independence, and productivity in older age [ 10, 11].
The current predominant mathematical models of fast-tracking are based on the concepts of activity sensitivity, evolution, dependency and, sometimes, information exchange uncertainty, and aim to determine optimum activity overlaps.
The ICF recognises potential overlap in the concepts of activity with participation and hence classifies it across the same domain.
In the ICF model the concepts of activity and participation are differentiated, but in the classification these concepts are combined and there is a single list of domains covering various actions and life areas.
In a study examining similar concepts of activity limitation among cancer patients, the percent experiencing any difficulties ranged from 18.0 to 70.0%, depending on the type of cancer, but was only 30.0% overall [ 18].
The concept of activities in the ICF refers to the performance of specific tasks, and participation reflects involvement in life situations.
Under the notion of this model, community integration was conceptualized to comprise four factors, including "assimilation," "support," "occupation," and "independent living," and each had specific indicators consistent with the ICF's concept of "activities and participation".
With regard to the concept of activity in a more global sense, it appears that being active is important for elderly people.
3. Wertsch, Concept of Activity, 7.
