Effects of intergenerational contact on social capital in community-dwelling adults aged 25-84 years: a non-randomized community-based intervention.

BACKGROUND: Accumulating social capital in urban areas is essential to improve community health. Previous studies suggested that intergenerational contact may be effective for enhancing social capital. However, no study has examined the effect of intergenerational contact on social capital through a population-based evaluation. This study aimed to investigate the effects of a community-based intervention to increase the frequency of intergenerational contact on social capital among adults aged 25-84 years. METHODS: This study used a non-randomized controlled trial design to conduct a community-based intervention (from March 2016 to March 2019). The study area was Tama ward, Kawasaki city, Kanagawa, Japan. The area comprises five districts; one district was assigned as the intervention group and the other four districts as the control group. We provided the intervention to residents in the intervention group. The intervention comprised three phases: Phase 1 was the preparation term (organizing the project committee); Phase 2 was the implementation term (trained volunteer staff members, conducted the intergenerational greeting campaign, and held intergenerational contact events); and Phase 3 was the transition term (surrendering the lead role of the project to the city hall field workers). In the control group, field workers provided public health services as usual. We conducted mail surveys in September 2016 and November 2018 to assess the effects of the intervention on social capital during Phase 2. Eligible participants were randomly selected from community-dwelling adults aged 25-84 years according to age (10,620 control group individuals and 4479 intervention group individuals). We evaluated social trust, norm of reciprocity, and social support as outcome variables. RESULTS: In total, 2518 participants completed both surveys and were analyzed (control group: 1727; intervention group: 791). We found that social trust (coefficient = 0.065; 95% confidence interval [CI]: 0.006, 0.125) and norm of reciprocity (coefficient = 0.084; 95% CI: 0.020, 0.149) positively changed in the intervention group compared with the control group. CONCLUSIONS: This community-based intervention may contribute to sustaining and improving social capital among community-dwelling adults. TRIAL REGISTRATION: UMIN000046769 (UMIN-CTR); first registered on January 28, 2022 (retrospectively registered).

[The relationship between intra- and inter-generational exchange and mental health among young and older adults].

Objective　The purpose of this study was to examine the relationship between intra- and inter-generational exchange and mental health among young adults aged 25-49 years and older adults aged 65-84 years.Methods　In 2016, a community-based, cross-sectional survey was conducted. A total of 3,334 young adults (valid response rate: 24.6%), and 3,116 older adults (valid response rate: 46.0%) completed the survey and were included in the analysis. Their mental health was evaluated using the World Health Organization-Five Well-Being Index (WHO-5), and those who scored under 13 or scored less than one on any item were considered to have poor mental health. To evaluate the intra- or inter-generational exchange, participants were asked about their frequency of interaction with people aged 20-49 years or aged ≥70, excluding family and co-workers. Young adults who interacted with people aged 20-49 years or older adults who interacted with people ≥70 were classified as "having intra-generational exchange," while young adults who interacted with people ≥70 years or older adults who interacted with people aged 20-49 years were classified as "having intergenerational exchange." Therefore, individuals who interacted with both generations were classified as "having multi-generational exchange," and those who did not interact with any generation were categorized as "no exchange." We conducted a logistic regression analysis that included mental health as a dependent variable, intra- and inter-generational exchange as independent variables, and gender, age, educational attainment, marital status, living situation, subjective economic status, social participation, employment, self-rated health, and Instrumental Activity of Daily Living as covariates.Results　Of the 3,334 young adults, 61.5% were mentally healthy, 51.3% had intra-generational exchange, 21.9% had inter-generational exchange, 16.5% had multi-generational exchange, and 42.7% did not have any exchange. Of the 3,116 older adults, 65.8% were mentally healthy, 67.9% had intra-generational exchange, 34.3% had inter-generational exchange, 29.9% had multi-generational exchange, and 21.1% did not have any exchange. A logistic regression analysis revealed that "having intra-generational exchange" and "having intergenerational exchange" were significantly related to better mental health in both young adults (intra-generational; Odds ratios (OR) 1.19, 95% confidence intervals (CI) 1.10-1.30: inter-generational; OR 1.13, 95% CI 1.03-1.25) and older adults (intra-generational; OR 1.15, 95% CI 1.02-1.29: inter-generational; OR 1.46, 95% CI 1.30-1.65). Therefore, "having multi-generational exchange" was more strongly related to better mental health compared with "only having intra-generational exchange."Conclusion　Among young and older adults, intra- and inter-generational exchange were related to better mental health, and multi-generational exchange showed the strongest relationship with better mental health.

[Community Child-Rearing Support Scale: Applicability across generations and differences in the supportive behaviors among generations].

Objectives　Using the Community Child-Rearing Support Scale (CCRSS), which was developed for older adults, we examined 1) the reliability and validity of the scale for multiple generations, as well as the generational differences in the 2) degree and content of supportive behaviors for child rearing and 3) correlates of the behavior, in conjunction with gender differences.Methods　A mail survey was conducted with residents aged 25-84 years who were randomly selected from two cities in Tokyo and the surrounding areas, and responses were obtained from 8918 residents (response rate: 33%). The respondents were grouped as follows: old-aged (65-84 years), middle-aged (50-64 years), and young-aged (25-49 years). We performed the following analyses by age group and gender: 1) Cronbach's reliability coefficient and a confirmatory factor analysis of the CCRSS, 2) analysis of variance of the total CCRSS scores and scores of the three subscales ("children's security and sound growth," "instrumental support to parents," and "emotional support to parents"), and 3) a multiple regression analysis of the total scores in which various individual characteristics were introduced as explanatory variables.Results　The reliability coefficient was over 0.85 for each age group, and the factor analysis showed good model fitness. Compared to the middle- and young-aged groups, the old-aged group was more likely to provide support for "children's security and sound growth," and equally (for women) or more likely (for men) to provide "emotional support to parents," thereby resulting in the highest total score among the three generations. The mean score of "instrumental support to parents," such as taking care of a child, was the highest for young women, although the score was low overall. Having a child or grandchild under 13 years old and stronger generativity were positively associated with child-rearing support for all age groups; however, the degree of associations varied across the groups. While having a child was strongly associated with support among the young-aged group, the association between support and generativity was stronger for older groups. Moreover, participation in neighborhood associations or volunteer groups and high school or lower education were associated with more support among all age groups, whereas living in rental apartments was associated with less support among the young-aged group.Conclusion　Our findings suggest that the CCRSS can be used for multiple generations and that old people play an important role in child rearing in the community. We found both differences and similarities between generations with respect to the correlates of child-rearing support.

Which part of community social capital is related to life satisfaction and self-rated health? A multilevel analysis based on a nationwide mail survey in Japan.

This paper aims to clarify the association between various social capital components at the municipal level (community social capital) and two quality-of-life factors at the individual level [individual self-rated life satisfaction and self-rated health (SRH)] based on data from a nationwide social capital survey that the authors carried out in 2013 in Japan (N = 3406 in 99 municipalities). The survey covers residents in Japan between the ages of 20 and 79 years. We focus on both contextual social capital and household income inequality in terms of the Gini coefficient at the municipality level since, to the best of our knowledge, no paper has explicitly dealt with municipalities in Japan as the units of contextual social capital and the Gini. Our analyses show that the subjective life satisfaction of individuals, after controlling for socioeconomic status and health at the individual level, is associate with both an income gap and social capital at the municipal level. Every component of community social capital in this study except for generalized reciprocity, both cognitive (generalized trust, particularized trust, and particularized reciprocity), and structural (three types of group participation and daily contacts with neighbors, friends/acquaintances, and colleagues), and the Gini coefficient on earned income were associated with self-rated life satisfaction at the individual level with statistical significance. However, SRH is associated only with cognitive social capital at the community level. SRH has no significant association with structural components of community social capital or with a community income gap in terms of the Gini coefficient on personal income. Judging from the results of estimates in the study, most of the components of community social capital at the municipal level seem to play an important role in enhancing self-rated life satisfaction. Life satisfaction may be associated with the broad atmosphere of the municipal level where one resides, while SRH is associated with cognitive social capital rather than structural social capital. However, the difference in the impact of contextual social capital between the two QOL indices may indicate the importance of considering a proper contextual level that is suitable for the outcome.

Development of a new direct core build-up method using a hollow fiber-reinforced post.

We have developed a new direct construction method for core build-up starting with the hypothesis that an improvement in pullout strength and a decrease in the number of voids in the restorative material will become possible by filling a hollow fiber reinforced post with the restorative material from the bottom of the root canal. For the pullout test, the hollow post was fixed to the head of a mixing tip and inserted into the bottom of a cylinder. The restorative material was then injected through the hollow post. The pullout load of the hollow posts was significantly higher than that of the solid fiber posts. The number of voids observed in the restorative material when using the hollow post was about 1/5 of that in the case of the solid post.