The Clinical Frailty Scale

Rebecca Rigney

The proportion of older adults is increasing worldwide. Currently, there are over 1 million people in Ireland over the age of 60 [1], with people over 60 representing 1 in 4 people in Ireland. Frailty can be described as a progressive, age-related, functional decline, which confers extreme vulnerability to endogenous and exogenous stressors, leading to increasing risk of adverse health outcomes [2].

Frailty prevalence among older patients in the Emergency Department (ED) is high, with up to two thirds of patients aged 65 years or older living with frailty. Identification of frailty in the ED has been largely advocated. It can however prove challenging as it requires acquiring data regarding the patient’s state prior to the current acute episode. Such data is not always readily available since patients are sometimes unable to communicate reliably, if at all. Prehospital assessment of frailty by paramedics is currently understudied. Since paramedics frequently respond at patients’ homes, they may have a more thorough understanding of the environment patients live in. Thus, prehospital assessment of frailty could be more accurate than ED assessment [3].

The Clinical Frailty Scale (CFS) is a straightforward and accessible tool that can be used to quickly and simply assess frailty. It has been validated in adults aged over 65 years. This tool can help optimize quality of life outcomes for geriatric patients. The CFS is easy and quick to administer in a clinical setting. It requires data collection by observing the patient mobilise and inquiring about their habitual physical activity and ability.

The clinicians assess whether the patient can independently perform tasks such as bathing, dressing, housework, going upstairs, going out alone, going shopping, taking care of finances, taking medications, and preparing meals. A person with a score ≥of 5 is considered frail [4].

The use of the CFS in the prehospital environment has not been reported often and has scarcely been assessed [5]. There is therefore a knowledge gap regarding the use of the CFS in the prehospital setting. The goals of this study were to assess the inter-rater reliability and accuracy of frailty assessment using the CFS and to identify factors associated with accurate CFS assessment among paramedics.

This was a cross-sectional study with paramedics exposed to 30 clinical vignettes created from real-life situations. There was no teaching intervention prior to the study and paramedics were only provided with a version of the CFS with definitions and pictograms. The primary outcome was the inter-rater reliability of frailty assessment. The secondary outcome were the accuracy of the assessment compared with the reference CFS, using specific definitions (inaccurate, under-assessment and over-assessment), and factors associated with accurate CFS assessment. An assessment was considered accurate if the paramedic assigned the same CFS level as the reference. Overassessment and underassessment were defined with regard to the reference CFS level.

A total of 56 paramedics completed the assessment. The overall assessment was found to have good inter-rater reliability (ICC = 0.87 [95%CI 0.81–0.93]). The overall accuracy was moderate at 60.6% (95%CI 54.9–66.1) when considering the full scale. It was however much higher (94.8% [95%CI 92.0–96.7] when close assessments were considered as accurate. The only factor associated with accurate assessment was field experience.

To conclude, the assessment of frailty by paramedics was reliable in this vignette-based study. However, the accuracy deserved to be improved. Future research should focus on the clinical impact of these results and on the association of prehospital frailty assessment with patient outcomes.



  1. O’Connor, N and Murphy, M A (2022) The State of Ageing in Ireland 2022 – Reframing Ageing. Dublin, Age Action Ireland.
  2. World Health Organization. World report on aging and health. Luxembourg: WHO; 2015
  3. Fehlmann, C.A., Stuby, L., Graf, C. et al. Assessment of frailty by paramedics using the clinical frailty scale - an inter-rater reliability and accuracy study. BMC Emerg Med 23, 121 (2023).
  4. Mendiratta P, Schoo C, Latif R. Clinical Frailty Scale. [Updated 2023 Apr 23]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from:
  5. Paul Bernard, Grace Corcoran, Lawrence Kenna, Claire O’Brien, Peter Ward, William Howard, Laura Hogan, Rebecca Mooney, Siobhan Masterson, Is Pathfinder a safe alternative to the emergency department for older patients? An observational analysis, Age and Ageing, Volume 50, Issue 5, September 2021, Pages 1854–1858,