Activity limitations are difficulties an individual has in the execution of an activity.

The performance of an activity is what the individual does in his or her current environment. The environment includes all aspects of the physical, social and attitudinal world. Activity limitation varies with the environment and is assessed in relation to a particular environment and in the absence or presence of assistance, including aids and equipment.

In time, a related and more generic data element may be developed. In the meantime, the addition of 'functioning, disability and health' to the concept of 'ability' indicates that the current concept is based on the concept and framework developed by World Health Organization to assist in the classification and description of functioning and disability, as contained in the ICF.

The ICF recognises two constructs that can be used with 'Activities and Participation': performance and capacity. 'Performance' is what the person does in their usual environment. 'Capacity' describes 'an individual's ability to execute a task or an action in a standardised environment, where a standardised environment may be:

• an actual environment commonly used for assessment in test settings; or
• in cases where this is not possible, an assumed environment which can be thought to have a uniform impact' (WHO 2001).

The standardised environment has not been generally operationalised. However, the recognition of these two constructs in the ICF underscores the importance of recording the environment in which activities are being performed.

This glossary item is based on the International Classification of Functioning, Disability and Health (ICF). The ICF was endorsed by the World Health Assembly in 2001 as a reference member of the WHO Family of International Classifications and of the Australian Family of Health and Related Classifications (endorsed by the National Health Information Management Group in 2002).
The ICF provides a framework for the description of human functioning and disability. The components of ICF are defined in relation to a health condition. A health condition is an ‘umbrella term for disease (acute or chronic), disorder, injury or trauma’ (WHO 2001). A health condition may be recorded, for example, as Episode of care principal diagnosis, code (ICD-10-AM 3rd Ed) ANN{.N[N} and Episode of care additional diagnosis, code (ICD-10-AM 3rd Ed) ANN{.N[N}.

World Health Organization (WHO) 2001. ICF: International Classification of Functioning, Disability and Health. Geneva: WHO

Australian Institute of Health and Welfare (AIHW) 2003. ICF Australian User Guide Version 1.0. Canberra: AIHW