Evaluation of work disability and the international classification of functioning, disability and health: what to expect and what not

Background: Individuals who are sick and unable to work may receive wage replacement benefits from an insurer. For these provisions, a disability evaluation is required. This disability evaluation is criticised for lack of standardisation and transparency. The International Classification of Functioning, Disability and Health (ICF) was developed to express the situation of people with disability. We discuss potential benefits of the ICF to structure and phrase disability evaluation in the field of social insurance. We describe core features of disability evaluation of the ICF across countries. We address how and to what extent the ICF may be applied in disability evaluation. Discussion: The medical reports in disability evaluation contain the following core features: health condition, functional capacity, socio-medical history, feasibility of interventions and prognosis of work disability. Reports also address consistency, causal relations according to legal requirements, and ability to work. The ICF consists of a conceptual framework of functioning, disability and health, definitions referring to functioning, disability and health, and a hierarchical classification of these definitions. The ICF component 'activities and participation' is suited to capture functional capacity. Interventions can be described as environmental factors but these would need an additional qualifier to indicate feasibility. The components 'participation' and 'environmental factors' are suited to capture work requirements. The socio-medical history, the prognosis, and legal requirements are problematic to capture with both the ICF framework and classification. Summary: The ICF framework reflects modern thinking in disability evaluation. It allows for the medical expert to describe work disability as a bio-psycho-social concept, and what components are of importance in disability evaluation for the medical expert. The ICF definitions for body functions, structures, activity and participation, and environmental factors cover essential parts of disability evaluation. The ICF framework and definitions are however limited with respect to comprehensive descriptions of work disability.