Derivation and Validation of the Detection of Indicators and Vulnerabilities for Emergency Room Trips Scale for Classifying the Risk of Emergency Department Use in Frail Community‐Dwelling Older Adults

OBJECTIVES: To develop and validate a prognostic case finding tool that classifies the risk of emergency department (ED) use in an older home care population. DESIGN: Population-based retrospective cohort study using routinely collected data from home care clinical assessments linked prospectively to ED records. SETTING: Ontario and the Winnipeg Regional Health Authority, Canada. PARTICIPANTS: Older adults living at home and expected to receive in-home services for at least 60 days (N = 361,942). MEASUREMENTS: One or more ED visits within 6 months after an in-home clinical assessment was used as the main dependent measure. Ninety-five person-level risk measures from a clinical assessment instrument were selected as potential independent variables. The Detection of Indicators and Vulnerabilities for Emergency Room Trips (DIVERT) Scale was derived using recursive partitioning analyses informed by a multinational clinical panel. RESULTS: Overall, 41.2% had one or more ED visits within 6 months of their in-home assessment. Previous ED use and cardiorespiratory symptoms, cardiac conditions, and specific geriatric syndromes were predictors within the six-level DIVERT Scale. The scale provided adequate risk differentiation for case finding, with an area under the receiver operating characteristic curve of 0.62 (95% confidence interval = 0.61-0.62) and distinct risk gradients between risk scores. The multilevel validation demonstrated consistent performance across geographic and participant clusters. CONCLUSION: The DIVERT Scale is a valid case-finding tool for ED use in older home care clients. It may be suitable for preemptively and systematically risk-stratifying individuals or groups for additional assessment, case management, and preventative interventions. It may also be suitable for the stratification and adjustment of performance metrics.