Objective: This study aimed to provide a psychometric evaluation of the Japanese version of the Ten-Item Personality Inventory (TIPI-J), and was conducted to confirm the concurrent validity, internal consistency, and test–retest reliability of the measure. Methods: A total of 520 middle-aged (40–64 years old) and 312 older adults (65–79 years old) participated in this study. Participants were registered research volunteers with an internet research company. The TIPI-J assesses the Big Five personality traits (Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness). The NEO-Five-Factor Inventory (NEO-FFI) was used to test concurrent validity. Results: Correlations of corresponding trait measures for the TIPI-J and NEO-FFI ranged from 0.45 (Openness) to 0.70 (Extraversion) for middle-aged, and from 0.33 (Openness) to 0.67 (Neuroticism) for older adults. The correlation values of Openness between the two scales were similar to those for the correlation between TIPI-J Openness and NEO-FFI Extraversion for both middle-aged and older adults, and that for the correlation between TIPI-J Openness and NEO-FFI Conscientiousness for older adults. The relationships between TIPI-J personality scores measured at a two-week interval ranged from 0.74 (Agreeableness) to 0.84 (Extraversion) for middle-aged and from 0.67 (Openness) to 0.78 (Neuroticism and Extraversion) for older adults. Conclusion: The TIPI-J has relatively acceptable concurrent validity, with the exception of Openness, which was considerably weaker than the other traits. The scale has relatively acceptable test–retest reliability. Thus, TIPI-J would be a useful instrument, roughly speaking, for assessing the Big Five personality traits among middle-aged and older adults.

The Japanese government has implemented a new screening program to promote measures to avoid worsening lifestyle-related diseases and frailty among the older population. In this effort, the government formulated a new health assessment questionnaire for the screening program of old-old adults aged ≥75 years. The questionnaire comprises 15 items, of which 12 address frailty, two address general health status, and one addresses smoking habits. This study examined the construct validity of this questionnaire, using the explanatory factor analysis (EFA) and confirmatory factor analysis (CFA). The data used in this study were drawn from a mail-in survey conducted in 2020 as part of the Septuagenarians, Octogenarians, Nonagenarians Investigation with Centenarians study. A total of 1576 respondents (range, 78–99 years of age) were included in the study. Although the EFA did not show an interpretable factor structure of the questionnaire with 15 items, the CFA using only 12 frailty-related items showed the goodness of fit for a higher-order factor “frailty”, and the five frailty-related sub-factors model was acceptable. These results suggest that the total score of the 12 frailty-related items in the questionnaire can be used as an indicator of the degree of “frailty”.

Inflammatory responses contribute to physical decline in older adults. Clinical studies have shown that the neutrophil-to-lymphocyte ratio (NLR), a marker of inflammation, is associated with physical decline. However, its association with physical function in community-dwelling older people is still unclear. Hence, we used cross-sectional data to investigate the relationship between NLR and physical function in community-dwelling older adults. Specifically, we analyzed data corresponding to 818 individuals (336 men and 482 women) aged ≥ 75 years, all of whom participated in comprehensive health examinations, including face-to-face interviews, biochemical analyses, and physical function tests. Using these data, we performed multivariable logistic regression analysis to assess the relationship between NLR and physical function, adjusting for sex, age, education, alcohol consumption, smoking, instrumental activity of daily living, body mass index, chronic disease, physical activity, serum albumin level, and depressive mood. The results showed that a higher NLR was associated with a lower grip strength, lower knee extension strength, and slower walking speed. Importantly, the relationship between NLR and physical function was maintained after adjusting for the confounding factors. Thus, we showed a significant association between NLR and physical function, supporting the use of NLR as a marker of physical function in community-dwelling older adults.

The objectives of this study were to explore how health information sources vary by functional health literacy levels and the relationship between health literacy and health behaviors among the old-old, community-dwelling adults. A cross-sectional study was used. The sample included 620 participants from a rural community in northern Japan. We used structured questionnaires to gather demographic information and assess health-related behaviors, information sources utilized, and functional health literacy. Functional health literacy scores were categorized into three groups, namely, low, middle, and high literacy. Individuals with limited health literacy were more likely to drink less alcohol, were less physically active, had less dietary variety, and had a low rate of medical check-ups. They were also less likely to use printed media, organization or medical procedure, electronic media, and accessed fewer health-related information sources. This study highlights the necessity of information tools that facilitate better access to information among older adults with limited health literacy.