Research on patient-facing chatbots based on large language models in the care of older people: a living systematic review. - Johnson JT; Duin JJ; Kuiper T; Drewes YM; Gussekloo J; van den Bos F; Lefebvre AEJL; Spruit M; van Dijk B; Mooijaart SP (European geriatric medicine, 2026)