Purpose: To identify self-reported disability measures developed for older adults by performing a systematic literature review and to compare the contents of all identified measures based on the International Classification of Functioning, Disability and Health (ICF).
Method: A broad systematic literature search was performed in March 2012 in the following databases: MEDLINE, EMBASE, CINAHL, PsycINFO and PROQOLID. Each item in the identified measures was extracted and linked to the ICF categories. A content comparison between measures was performed. The content density and diversity of each measure were assessed by calculating the content density ratio (the number of meaningful concepts divided by the number of items in each questionnaire) and content diversity ratio (the number of different ICF categories divided by the number of linked meaningful concepts), respectively.
Results: We reviewed 5622 published articles and identified 13 eligible measures. In total, 293 meaningful concepts from 265 items were extracted, of which, 270 concepts were linked to the ICF. A total of 62 different ICF categories were addressed. EARRS, FHS and SF-LLFDI had the highest content density ratio, while FHS and KI had the highest content diversity ratio. Different measures differed considerably in content.
Conclusions: The ICF can be used as a conceptual framework not only for assessing measures but also for developing new measures. According to this ICF-based content comparison, the contents of currently available measures for disability in older adults vary significantly from one another. Our study may provide useful information for the selection of suitable measures for a particular purpose, as well as the development of new measures.
Keywords: Disability; elderly; health; international classification of functioning.