Comparisons of latent factor region means of spatial ability based on measurement invariance

Empirical investigation was conducted to examine the measurement invariance of the Standardized Spatial Ability Test in three regions. A full line of invariance testing (for configure, factor loadings, intercepts, residuals, latent factor variances, latent factor covariances, and latent factor mean structure) was employed. Special treatment was applied for the non-normal and dichotomous data in the study. As the region invariance of the measurement model was sustained, the results from the two mean comparisons (the latent factor region means and the observed score region means) were the same accordingly. The establishment of measurement invariance of the measure can facilitate meaningful group comparisons on the same test structure and augment the measure's validity in generalization in large scale application and test development.