Employing the International Classifications of Functioning, Disability, and Health to identify relevant categories for disability evaluation in older adults from the research perspective: a systematic review.

Introduction: The objective of this study was to identify relevant aspects for disability evaluation used in scientific literature for older adults.

Evidence acquisition: We employed a systematic review methodology as outlined by the ICF Research Branch. The methodology consists of four steps: 1) identifying studies that focus on disability evaluation among older adults; 2) identifying disability measures used in these studies; 3) linking the concepts contained in these measures to ICF categories; 4) conducting frequency analysis.

Evidence synthesis: A total of 1942 concepts contained in disability measures from 137 studies were extracted. About 97.7% of the concepts could be linked, and 1862 concepts were linked to 52 second-level ICF categories. Of these, 44 categories found in at least 5% of the studies (range 5.1-85.4%) were selected to develop an outcome set that represents the relevant categories, including five categories in the Body Functions component and 39 categories from the Activities and Participation component.

Conclusions: The relevant categories identified in our study reflect the essential areas that measure disability for older adults, providing a scientific basis for developing an ICF Core Set for disability evaluation, in combination with further empirical study and expert survey. Information from the outcome set is also valuable for providing a standardized minimal set for disability measurement, which can be used for data comparison across different studies and the development of an ICF-based disability measurement tool.