Influenced by the social model, the World Health Organization (WHO) began to re-develop its classification (initially called ICDH-2, but now called ICF) in the late 1990s. This new classification facilitates a merge between the medical and social model and attempts to include environmental factors. Disability is now seen as:
an interaction between health conditions and contextual factors where both health and contextual factors may have an influence on the activities a disabled person can perform or the extent to which they can participate in the social world around them (and vice versa).
Disability is therefore understood as the extent to which performance of activities are limited and:
- activity is defined as everything that a person does;
- participation is defined as the interaction of impairments, disabilities and contextual factors and comprises all aspects of human life;
- contextual factors are defined as the complete background to a person’s life and living, including external environmental factors and internal personal factors.
The WHO argue that their new classification now operates a universal rather than a minority model of disability where everyone may have disability; disability is seen as a continuum rather than dichotomous and is understood as multi-dimensional. This universal model is based on the value of inclusion and rejects the view that disability is a defining feature of a separate minority group of people.