Community-based participatory research in a “Shitamachi” neighborhood in Tokyo: building social capital and relational spaces for community health

BACKGROUND: Community-Based Participatory Research (CBPR) offers a relational framework for bridging scientific inquiry and everyday life. Yet its adaptation to Japan’s urban contexts—where dense traditions coexist with social fragmentation—remains underexplored. METHODS: Since 2015, the YaNeSen CBPR has linked residents, physicians, and researchers in Tokyo’s historic Shitamachi district of Yanaka–Nezu–Sendagi to co-create health-promoting spaces grounded in local culture. Using ethnographic fieldwork, community asset mapping, and collaborative action, the team developed the “Mobile Yatai de Health Café”—a movable wooden stall that was intermittently deployed between 2016 and 2020 to serve coffee and invite spontaneous street-level dialogue between residents and care professionals. Follow-up interviews with 12 participants in 2021 were thematically analyzed to assess long-term transformations. RESULTS: Early engagement revealed temples, public baths, and alleys as “third places” sustaining social capital. The Mobile Yatai extended this ecology by generating salutogenic encounters that blurred boundaries between health, art, and everyday sociability. Interview narratives described the project as a “space of relational invitation” (kakawari-shiro) characterized by openness, serious play, and an ethics of non-obligation. Participants reported a broadened sense of health as relational, expressive, and experiential rather than biomedical. CONCLUSIONS: The YaNeSen CBPR demonstrates how culturally embedded, art-based collaboration can nurture “relational commons” that sustain well-being in aging urban communities. By valuing presence, ambiguity, and care over prescriptive intervention, this study reframes health as convivial coexistence through culturally embedded participatory art.