Comparison of ability-based and performance-based IADL evaluation of community-dwelling elderly using the Kihon Checklist and TMIG Index of Competence

Abstract

Aim: Elderly populations are evaluated on their ability to perform instrumental activities of daily living (IADL) using one of three subscales in the Tokyo Metropolitan Institute of Gerontology (TMIG) Index of Competence, while the Kihon Checklist - a tool developed to screen for frailty - is designed to measure actual task performance. This study examined the significance of performance-based evaluations. Methods: Using five items from the TMIG Index of Competence assessing ability, and three items included in the Kihon Checklist assessing performance, 124 community-dwelling elderly persons were evaluated in five daily task areas: using public transportation; shopping for daily necessities; handling bank accounts; paying bills; and preparing meals. Physical, psychological and social functioning were also assessed during the evaluations. Results: The study revealed discrepancies between participants' abilities and their performance levels of the same daily tasks. Of the respondents, 12.5% men and 13.4% women reported that "they could perform all three tasks on the Kihon Checklist, but in actuality did not perform at least one of them". This "borderline-performance group" indicated a lower functioning level than those who answered "they performed all tasks" in all three physical, psychological and social domains. However, this group indicated a higher functioning level than those reporting that it was "impossible to perform at least one task" in all three domains. Conclusion: Study findings suggested that borderline-performance was related to the early stage of functional decline. The performance-based IADL evaluation is an effective screening tool for preventive declines in daily task performance.