First order or higher order general factor?

Abstract The Schmid‐Leiman decomposition of a hierarchical factor model converts the model to a constrained case of a bifactor model with orthogonal common factors that is equivalent to the hierarchical model. This article discusses the equivalence and near‐equivalence of the hierarchical and bifactor models and the implications of the difficulty of distinguishing between these models because of low power in samples commonly found in academic research.