Psychometric Testing of the Updated Self-Care of Heart Failure Index Version 8.0 Using Item Response Theory

Self-care is essential in adults living with heart failure (HF). The landscape of HF management has changed considerably over the past few years, and as such, we modernized an existing measure of HF self-care. The purpose of this study was to test the psychometric properties of the revised Self-Care of Heart Failure Index (SCHFI) version 8.0 using item response theory.

A cross-sectional descriptive study was designed and conducted in the United States to test the psychometric properties of the 26-item SCHFI 8.0. We used item response theory-based approaches to determine which items contributed sufficient information to our understanding of the 3 behavioral domains: self-care maintenance (ie, routine healthy behaviors), self-care monitoring (ie, monitoring for signs and symptoms), and self-care management (ie, responding to signs and symptoms when they occur). We also used classic test theory approaches to compare results between the SCHFI 8.0 and prior versions.

Participants included 217 adults with HF (mean age = 43 ± 15 years; 54.4% male, 56.2% White, 58% HF with reduced ejection fraction). Based on item response theory, items providing insufficient information within each behavioral domain were identified and removed from the SCHFI 8.0 during recalibration resulting in an abbreviated 23-item measure. The SCHFI 8.0 was most reliable at middle-to-low levels of each behavioral domain. Based on classic test theory, the self-care maintenance, self-care monitoring, and self-care management domains had Cronbach α values of 0.86, 0.90, and 0.88, respectively, and the theoretical structure of the SCHFI 8.0 was confirmed with factor analysis.

The 23-item SCHFI 8.0 is a valid, reliable and abbreviated measure that is ready to use and freely available on the website www.self-care-measures.com.