NOTE 1 An observation of a health state is a health condition. A health state may possibly give way to more than one observation, resulting in more than one health condition. The underlying health state is nevertheless present even if not perceived by an observer, for example, the subject of care having a cancer before it gives symptoms.
NOTE 2 In ICF (the International Classification of Functioning, Disability and health) of the WHO, the concept of health is described. ICF identifies five health components; body function, body structure, activity, participation and environmental factors.