The Problem With Cronbach’s Alpha

Knowledge of a scale's dimensionality is an essential preliminary step to the application of any measure of reliability derived from classical test theory—an approach commonly used is nursing research. The focus of this article is on the applied aspects of reliability and dimensionality testing. Throughout the article, the Self-Care of Heart Failure Index is used to exemplify real-world data challenges of quantifying reliability and to provide insight into how to overcome such challenges.