Assessing the impact of health conditions using the ICF.

PURPOSE: People may suffer from diseases and a variety of health conditions, but a full understanding of the experience of their health condition also requires comprehensive information about the impact of the disease or the health condition on the person. This article operationalises the impacts of health conditions as classified in the International Classification of Diseases (ICD) in terms of the concept of functioning as found in the International Classification of Functioning, Disability and Health (ICF). It identifies a set of ICF categories as the functioning properties - to describe the impact of health conditions generically across health conditions to be jointly used with the ICD.
METHOD: The ICF categories to characterise the functioning properties of any health condition have been selected from three main generic health profile instruments: The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0), the World Health Survey (WHS) Questionnaire and a list of candidate categories of the generic ICF core set.
RESULTS: A set of ICF categories to describe the impact of a health condition is presented according to specific functioning domains.
CONCLUSIONS: The joint use of the ICD and the ICF through the list of functioning properties and in the context of ICD-11 development captures the valuable synergy of the two classifications. It enhances patient management, intervention design and the reporting of health. It also enables us to distinguish severity of disease from its impacts. The ICD-ICF joint use creates a shared formal representation across the continuum of care for health information system implementation.