Does the Bayley-4 measure the same constructs across girls and boys and infants, toddlers, and preschoolers?

This study tested the assumption that the Bayley Scales of Infant and Toddler Development, Fourth Edition (Bayley-4) functions similarly for boys and girls and for four age groups. The Bayley-4 American norming sample of 1,700 children ages 0-42 months (3.5 years) was used, which included 50% boys and girls. Fifty-three percent of the children identified as White, 22.1% as Hispanic, 12.5% as Black, 8.5% as other, and 4.0% as Asian. A confirmatory factor analysis demonstrated the three-factor structure of cognitive, language, and motor abilities fit the data well (comparative fit index = .99, root-mean-square of error of approximation = .08, standardized root-mean-square residual = .02) and fit significantly better than the two- and one-factor models. The correlations between the latent factors were moderate (