Figure 1: World Health Organization model of the international classification of functioning, disability and health for children and youth (ICF-CY). Body functions are physiological functions of body systems (including psychological functions). Body structures are anatomical parts of the body such as organs, limbs, and their components. Impairments are problems in body function or structure such as a significant deviation or loss. Activity is the execution of a task or action by an individual. Participation is involvement in a life situation. Activity limitations are difficulties an individual may have in executing activities. Participation restrictions are problems an individual may experience in involvement in life situations. Environmental factors make up the physical, social, and attitudinal environment in which people live and conduct their lives. Personal factors are features of the individual that are not part of a health condition or health state.