The ADLs are detected by a battery of questions (established by the Organization for Economic Co-operation and Development - OECD) used in population surveys to asses the degree of individual autonomy. They measure the ability to perform activities and basic functions deemed essential in daily living and are used to study disability. Three key dimensions of disability can be outlined: daily living functions, including personal care (washing, dressing, bathing or showering, eating); physic, mainly related to mobility and walking (walking, climbing up and down the stairs, picking up objects from the floor) that, in extreme situations, it appears as confinement, ie permanent constriction of the individual in a bed, a chair or a house; and communication, including speech, vision and hearing. The battery was prepared according to the "International Classification of Impairments, Disabilities and Handicaps" (ICIDH, 1980) of the World Health Organization.