Comparison of physical activity questionnaires for the elderly with the International Classification of Functioning, Disability and Health (ICF) – an analysis of content

Table 2 Example of the hierarchical taxonomy system of the ICF

Code	Category	Level
d	Activities and Participation	Component level
d4	Mobility	1^st level item
d450	Walking	2^nd level item
d4501	Walking long distances	3^rd level item

ISSN: 1471-2458