Predictive validity of the Questionnaire for Medical Checkup of Old‐Old for all‐cause mortality and disability incidence

Aim The Questionnaire for Medical Checkup of Old‐Old (QMCOO) has been used nationwide in Japan as part of the health checkup for latter‐stage older adults since the financial year 2020. Although the QMCOO is useful in screening for frailty, its cutoff values for predicting adverse health outcomes have rarely been assessed. Therefore, this study aimed to calculate the cutoff values for predicting all‐cause mortality and disability incidence and to evaluate their predictive validity. Methods This study included 3837 health checkup recipients aged ≥75 years residing in Higashiura Town, Aichi Prefecture, Japan. The health checkup was conducted from June 1, 2020, to January 31, 2021. Mortality and disability incidence were analyzed separately. For the latter, participants with a disability history were excluded, leaving 3040 available for analysis. Results During the follow‐up of 11 191 and 8550 person‐years, 276 died and 438 developed a disability, respectively. The areas under the receiver operating characteristic curve (95% confidence intervals) for all‐cause mortality and disability incidence were 0.68 (0.65–0.71) and 0.66 (0.63–0.68), respectively, with QMCOO cutoff values at 3/4 and 2/3 points. Cox proportional hazard models adjusted for age, sex, body mass index, self‐reported diseases, and frequency of alcohol consumption demonstrated the predictive validity of those cutoff values. Conclusions The optimal cutoff value of the QMCOO for predicting all‐cause mortality was 3/4, while the optimal cutoff value for predicting disability incidence was 2/3 among an older Japanese population. Geriatr Gerontol Int 2024; 24: 1203–1209. We examined the predictive validity of the Questionnaire for Medical Checkup of Old‐Old (QMCOO) in the national health examinations for older adults. The study showed that the QMCOO had acceptable discriminatory power and may be useful for predicting all‐cause mortality in community‐dwelling older adults.