Comparing frailty prevalence between countries: validation of the Global Burden of Disease study Frailty Index (GBD-FI) in the survey of health, ageing and retirement in Europe, O'Donovan, Mark R., Devleesschauwer Brecht, Sezgin Duygu, Liew Aaron, Kabir Zubair, and O'Caoimh Rónán , Age Ageing, 2023 Nov 02, Volume 52, Issue 11, (2023)