Toward a Self-Report Cumulative Deficits Frailty Scale (Sr-CDFS): Development and Clinimetric Properties of a Novel Frailty Scale.

Background and purpose: Frailty, a multidimensional syndrome, is linked with heightened risk of adverse outcomes. Targeted physical therapy interventions for individuals with frailty have proven beneficial, underscoring the value of routine frailty assessment in both clinical and research settings. This study aimed to: (1) describe development of a simple self-report cumulative deficits frailty scale (Sr-CDFS); (2) establish the criterion validity of Sr-CDFS against the commonly used Fried's frailty scale and Study of Osteoporotic Fracture criteria (SOF); and (3) assess other concurrent validity and internal consistency of the new Sr-CDFS.

Methods: The study included 230 older adults (M age = 79.27 ± 7.42 years), with 76.5% being women. Outcome measures were: (1) validated frailty scales, including Fried's frailty phenotype, SOF, and Sr-CDFS; and (2) a battery of tests for impairment, activity limitations, and health status. Data analysis involved calculating frailty prevalence using the validated frailty scales. The clinimetric properties of the Sr-CDFS were assessed against validated frailty scales. Convergent and discriminative validity of the Sr-CDFS were examined. Internal consistency and structure were evaluated using Cronbach's alpha and exploratory factor analysis.

Results and discussion: No differences (P = .80) in frailty prevalence were found between Fried (26.1%) and SOF (25.2%) methods. The Sr-CDFS exhibited excellent internal consistency (Cronbach's alpha = .92), with reliability of questionnaire components (health, falls, physical, cognitive, socioemotional function) ranging from .73 (falls) to .90 (physical ability). Additionally, the Sr-CDFS demonstrated convergent and discriminative validity, with its total score and various parts correlating significantly with most outcomes (r = .25-.59, P < .05). Using K1-criterion and a scree plot, we identified a 5-factor solution that had a common variance of 63.9%.

Conclusion: The newly developed Sr-CDFS exhibits robust clinimetric properties with good-to-excellent reliability and validity. The newly developed Sr-CDFS has the potential to increase the feasibility of assessing frailty in clinical settings or large-scale epidemiological studies.