Sample Size Requirements for Bifactor Models

Despite the widespread application of bifactor models, little research has considered required sample sizes for this type of model. As universal sample size recommendations are often misleading, we illustrate how to determine sample size requirements of bifactor models using Monte Carlo simulations in R. Furthermore, we present results of an extensive simulation study investigating the effects of the number of specific factors and indicators, loading magnitude, the relative general factor strength, and the validity of the proportionality condition on sample size requirements. Although a sample size of 500 was often sufficient to obtain acceptable convergence rates and parameter estimates, the exact sample size requirements depended on various model characteristics.