The Validity and Reliability of Korean Frailty Index

Background: Frailty is a syndrome that involves decreased reserve capacity and loss of physiological function caused by aging. This study was done to develop a frailty index for the Korean elderly. Methods: The Korean frailty index 8-item questionnaire was established by a panel of experts from the Korean Geriatrics Society. Demographic characteristics, the cardiovascular health study (OHS) frailty index and the Korean frailty index were completed for 240 men and women over 65 years visiting three selected community senior's welfare centers from June 2009 to August 2009. Reliability was tested by internal consistency (Cronbach's alpha) and the test-retest reliability at a 2-week interval. Validity was tested by a criterion validity comparison between the CHS frailty index and the validity index estimated by the reliability index. Results: Cronbach's alpha was 0.65. The range of Kappa value for each item was 0.27-0.65. The Kappa value of the criterion validity comparison with the OHS index for the Korean frailty index was 0.5. The validity indexes for the items estimated by the reliability index ranged from 0.27-0.52 to 0.65-0.81. Conclusion: The Korean frailty index is a valid and reliable instrument. However, fine-tuning such as item-revision is needed prior to use in the practical setting.