Implementation science in care for older adults across healthcare settings: a scoping review.

BACKGROUND: Translating evidence into the routine care of older adults remains challenging. This scoping review mapped how implementation science theories, models, and frameworks (TMFs) were selected and used in research on the care of older adults across healthcare settings. METHODS: Following JBI guidance and PRISMA-ScR, AgeLine, CINAHL, PsycINFO, EMBASE, Emcare, and MEDLINE were searched for research involving older people (non‑Indigenous ≥ 65 years; Indigenous ≥ 50 years) that used implementation science and a TMF across healthcare settings that cared for older adults. Two reviewers independently screened and extracted data; characteristics and TMF use were summarised, descriptively, and content analysis was conducted to summarise rationales, applications, and contextual influences. RESULTS: From 12,767 records, 108 publications (2000-2023) were included. Studies were conducted mainly in the United States of America (29.8%) and Canada (15.8%) and were most often hospital-based (36.1%); few focused on community (3.7%) or home settings (3.7%). Qualitative designs were most common (44.4%). The most frequently applied individual TMFs were the consolidated framework for implementation research (CFIR), and the reach, effectiveness, adoption, implementation, and maintenance (RE-AIM) framework. These were followed by the theoretical domains framework (TDF), the promoting action on research implementation in health services (PARIHS) framework, and the normalisation process theory. Most of the publications reported on a standalone approach (86.1%). Most of the TMFs were not specific to the care of older adults, but were approaches applied across health and service contexts, with the normalisation process theory, the RE-AIM framework, and the theory of diffusion frequently applied in aged care facilities. Fewer than half of the publications reported the benefits (40.7%), limitations (13.9%), enablers (12.0%), or hindrances (22.2%) associated with the selected TMF. Twenty‑eight TMFs were absent. CONCLUSIONS: Implementation science in the care of older adults relies on broad, transferable determinant and evaluation frameworks (predominantly CFIR and RE-AIM framework), while largely neglecting staged process models that guide active translation. Research remains concentrated in hospital settings and Western nations, creating a significant structural mismatch with modern healthcare trajectories that emphasise home- and community-based care. Furthermore, current applications prioritise professional and organisational processes over the relational realities of care, routinely failing to integrate the perspectives of minoritised populations, families, and informal carers. To mature, the field must pivot towards decentralised settings, integrate longitudinal sustainability metrics, and actively position older adults and carers as implementation leaders. REGISTRATION: Unregistered.