Questionnaire for Medical Checkup of Old‐Old is non‐inferior to the Kihon Checklist in screening frailty among independent older adults aged 75years and older: The Itabashi Longitudinal Study on Aging

AimThe Questionnaire for Medical Checkup of Old‐Old (QMCOO) is a 15‐item dichotomous questionnaire developed for the early detection and intervention of frailty in a nationwide health checkup program targeting the old‐old (i.e. aged ≥75 years). The Kihon Checklist (KCL) is a 25‐item questionnaire widely used for screening and self‐monitoring frailty status in administrative settings. With fewer items than the KCL, the QMCOO might expedite the frailty screening process. This study tested whether the QMCOO shows noninferiority in detecting frailty compared with the KCL.MethodsOverall, 645 participants aged ≥75 years in the Itabashi Longitudinal Study on Aging were assessed for their frailty status according to the revised Japanese version of the Cardiovascular Health Study criteria. They also completed the QMCOO and the KCL simultaneously. We compared the discriminative performance of the two questionnaires using non‐inferiority testing with an operationally defined non‐inferiority margin of 10% of the area under the receiver operating characteristic curve computed from the KCL.ResultsThe prevalence of frailty was 8.8%. The area under the receiver operating characteristic curve for the QMCOO in determining frailty was 0.76 (95% CI 0.70, 0.82), and the corresponding area under the receiver operating characteristic curve for the KCL was 0.77 (95% CI 0.69, 0.84). The QMCOO was not inferior to the KCL for frailty discrimination (P for non‐inferiority = 0.006).ConclusionsThe accuracy of the QMCOO for determining frailty was not inferior to that of the KCL. The QMCOO might be more acceptable and useful, as it can be applied in a shorter time with fewer questions than the KCL. Geriatr Gerontol Int 2024; 24: 176–181.