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

Abstract

ObjectivesTo 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 SettingThis 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. ResultsWe 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. ConclusionEASY-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.