Construct validity and reliability of a two-step tool for the identification of frail older people in primary care

Abstract

Objectives: To study the reliability and construct validity of the EASY-Care Two-step Older persons Screening (EASY-Care TOS), a practice-based tool that helps family physicians (FPs) to identify their frail older patients.

Study design and setting: This validation study was conducted in six FP practices. We determined the construct validity by comparing the results of the EASY-Care TOS with other commonly used frailty constructs [Fried Frailty Criteria (FFC), Frailty Index (FI)] and with other related constructs (ie, multimorbidity, disability, cognition, mobility, mental well-being, and social context). To determine interrater reliability, an independent second EASY-Care TOS assessment was made for a subpopulation.

Results: We included 587 older patients (mean age 77 ± 5 years, 56% women). According to EASY-Care TOS, 39.4% of patients were frail. EASY-Care TOS frailty correlated better with FI frailty (0.63) than with FFC frailty (0.52). A high correlation was found with multimorbidity (0.50), disabilities (0.53), and mobility (0.55) and a moderate correlation with cognition (0.31) and mental well-being (0.38). Reliability testing showed 89% agreement (Cohen's κ 0.63) between EASY-Care TOS frailty judgment by two different assessments.

Conclusion: EASY-Care TOS correlated well with relevant physical and psychosocial measures. Accordingly, these results show that the EASY-Care TOS identifies patients who have a wide spectrum of interacting problems.

Keywords: Assessment; Construct; Elderly; Family physician; Frailty; Reliability.