Clegg A, Young J, Iliffe S, et al. Frailty in elderly people. Lancet. 2013;381(9868):752–62.

Article  PubMed  PubMed Central  Google Scholar 

Ye L, Nieboer D, Yang-Huang J, et al. The association between frailty and the risk of medication-related problems among community-dwelling older adults in Europe. J Am Geriatr Soc. 2023;71(8):2485–94.

Article  PubMed  Google Scholar 

Lam JYJ, Barras M, Scott IA, et al. Scoping review of studies evaluating frailty and its association with medication harm. Drugs Aging. 2022;39(5):333–53.

Article  PubMed  PubMed Central  Google Scholar 

Walston J, Buta B, Xue QL. Frailty screening and interventions: considerations for clinical practice. Clin Geriatr Med. 2018;34(1):25–38.

Article  PubMed  PubMed Central  Google Scholar 

Vermeiren S, Vella-Azzopardi R, Beckwée D, et al. Frailty and the prediction of negative health outcomes: a meta-analysis. J Am Med Dir Assoc. 2016;17(12):1163.e1-17.

Article  PubMed  Google Scholar 

Daunt R, Curtin D, O’Mahony D. Polypharmacy stewardship: a novel approach to tackle a major public health crisis. Lancet Healthy Longev. 2023;4(5):e228–35.

Article  PubMed  Google Scholar 

O’Caoimh R, Sezgin D, O’Donovan MR, et al. Prevalence of frailty in 62 countries across the world: a systematic review and meta-analysis of population-level studies. Age Ageing. 2021;50(1):96–104.

Article  PubMed  Google Scholar 

Statistical Office of the European Union (Eurostat). Population structure and ageing. Available from: https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Population_structure_and_ageing. Accessed 7 May 2026.

Nielsen CR, Ahrenfeldt LJ, Jeune B, et al. Healthy life expectancy by frailty state in Europe from 2004 to 2015: findings from SHARE. Eur J Public Health. 2021;31(3):554–60.

Article  PubMed  PubMed Central  Google Scholar 

Lim A, Choi J, Ji H, et al. Frailty assessment using routine clinical data: an integrative review. Arch Gerontol Geriatr. 2022;99:104612.

Article  PubMed  Google Scholar 

Carrein M, Mehuys E, Lahousse L, et al. Development of a frailty screening tool using electronic community pharmacy records. Drugs Aging. 2024;41(12):989–1001.

Article  PubMed  Google Scholar 

Collins GS, Moons KGM, Dhiman P, et al. TRIPOD+AI statement: updated guidance for reporting clinical prediction models that use regression or machine learning methods. BMJ. 2024;385:e078378.

Article  PubMed  PubMed Central  Google Scholar 

Moons KG, Altman DG, Reitsma JB, et al. Transparent Reporting of a multivariable prediction model for Individual Prognosis or Diagnosis (TRIPOD): explanation and elaboration. Ann Intern Med. 2015;162(1):W1-73.

Article  PubMed  Google Scholar 

Berete F, Demarest S, Charafeddine R, et al. Linking health survey data with health insurance data: methodology, challenges, opportunities and recommendations for public health research. an experience from the HISlink project in Belgium. Arch Public Health. 2023;81(1):198.

Article  PubMed  PubMed Central  Google Scholar 

Nguyen D, Hautekiet P, Berete F, et al. The Belgian health examination survey: objectives, design and methods. Arch Public Health. 2020;78:50.

Article  PubMed  PubMed Central  Google Scholar 

Demarest S, Van der Heyden J, Charafeddine R, et al. Methodological basics and evolution of the Belgian health interview survey 1997–2008. Arch Public Health. 2013;71(1):24.

Article  PubMed  PubMed Central  Google Scholar 

Fried LP, Tangen CM, Walston J, et al. Frailty in older adults: evidence for a phenotype. J Gerontol A Biol Sci Med Sci. 2001;56(3):M146–56.

Article  CAS  PubMed  Google Scholar 

Romero-Ortuno R, Walsh CD, Lawlor BA, et al. A frailty instrument for primary care: findings from the Survey of Health, Ageing and Retirement in Europe (SHARE). BMC Geriatr. 2010;10:57.

Article  PubMed  PubMed Central  Google Scholar 

Romero-Ortuno R, Soraghan C. A frailty instrument for primary care for those aged 75 years or more: findings from the Survey of Health, Ageing and Retirement in Europe, a longitudinal population-based cohort study (SHARE-FI75+). BMJ Open. 2014;4(12):e006645.

Article  PubMed  PubMed Central  Google Scholar 

World Health Organization. ATC/DDD index: collaborating centre for drug statistics methodology. Norwegian Institute of Public Health. 2023. https://www.whocc.no/atc_ddd_index/. Accessed 30 May 2026.

Pratt NL, Kerr M, Barratt JD, et al. The validity of the Rx-Risk comorbidity index using medicines mapped to the Anatomical Therapeutic Chemical (ATC) classification system. BMJ Open. 2018;8(4):e021122.

Article  PubMed  PubMed Central  Google Scholar 

Vickers AJ, Elkin EB. Decision curve analysis: a novel method for evaluating prediction models. Med Decis Mak. 2006;26(6):565–74.

Article  Google Scholar 

Wolff RF, Moons KGM, Riley RD, et al. PROBAST: a tool to assess the risk of bias and applicability of prediction model studies. Ann Intern Med. 2019;170(1):51–8.

Article  PubMed  Google Scholar 

Moons KGM, Damen JAA, Kaul T, et al. PROBAST+AI: an updated quality, risk of bias, and applicability assessment tool for prediction models using regression or artificial intelligence methods. BMJ. 2025;388:e082505.

Article  PubMed  PubMed Central  Google Scholar 

Ramspek CL, Jager KJ, Dekker FW, et al. External validation of prognostic models: what, why, how, when and where? Clin Kidney J. 2021;14(1):49–58.

Article  PubMed  Google Scholar 

Best K, Shuweihdi F, Alvarez JCB, et al. Development and external validation of the Electronic Frailty Index 2 using routine primary care electronic health record data. Age Ageing. 2025;54(4):afaf077.

Article  PubMed  PubMed Central  Google Scholar 

Shah ND, Steyerberg EW, Kent DM. Big data and predictive analytics: recalibrating expectations. JAMA. 2018;320(1):27–8.

Article  PubMed  Google Scholar 

Collins GS, Dhiman P, Ma J, et al. Evaluation of clinical prediction models (part 1): from development to external validation. BMJ. 2024;384:e074819.

Article  PubMed  PubMed Central  Google Scholar 

Van Calster B, McLernon DJ, van Smeden M, et al. Calibration: the Achilles heel of predictive analytics. BMC Med. 2019;17(1):230.

Article  PubMed  PubMed Central  Google Scholar 

Su T-L, Jaki T, Hickey GL, et al. A review of statistical updating methods for clinical prediction models. Stat Methods Med Res. 2018;27(1):185–97.

Article  PubMed  Google Scholar 

Crutzen S, Schuling J, Hugtenburg JG, et al. Development and piloting of an algorithm to select older patients for different types of medication review. Front Pharmacol. 2019;10:217.

Article  PubMed  PubMed Central  Google Scholar 

Money A, MacKenzie A, Parchment A, et al. Evidence on non-pharmacological interventions for preventing or reversing physical frailty in community-dwelling older adults aged over 50 years: overview of systematic reviews. BMC Geriatr. 2025;25(1):183.

Article  PubMed  PubMed Central  Google Scholar 

Nimmons D, Clegg A, Walters K. Using the new electronic frailty index (eFI2) to aid frailty identification and management in primary care. Br J Gen Pract. 2025;75(755):249–50.

Article  PubMed  PubMed Central  Google Scholar