Abstract
This factor analytic study had two goals: to characterize relationships among sensorimotor, social and communication domains in infancy, and to look for qualitative change in those relationships across two developmental levels (or stages). Children were grouped according to level; Level II children had Bayley MAs 8-13 months and Level III children had MAs 14-21 months. All were from middle income families and had normal developmental histories.Tests used were an adaptation of the Uzgiris-Hunt Scales (AUHS) to measure sensorimotor skills, and the Early Social-Communication Scales (ESCS). The 13 scale scores (5 AUHS, 8 ESCS) were intercorrelated and then subjected to confirmatory factor analyses using the LISREL-V program.Three models were tested: a single general factor model; an oblique two-factor model (Object-skill and Person-skill factors); and an oblique three-factor model (Object-Cognitive, Social and Communication factors).For Level II, the three-factor model provided an adequate fit, the best of the three models. For Level III, the two-factor model provided the best fit but was statistically inadequate. At each level, specific skill correlations were all accounted for by the latent factor correlations. Overall, these results supported conceptual distinctions among the domains, and the notion of a common structural base for the domains.Evidence for qualitative change across levels was mixed. The Cognitive factor showed no change in that a model of equal loadings, errors and factor variance fit the groups' data. The Social factor showed some evidence for change; only the loadings were equal across groups. The Communication factor showed the best evidence for qualitative change; no aspect of the factor structure was equal across the groups. These results indicated that Communication skills are the domain in which qualitative change occurs in the transition from the first to second years of infancy.Overall, these results supported the utility of this analytic technique, provided some validation for the organization of the ESCS, and, most importantly, contributed to our understanding of the organization of and fundamental changes in infant behavior from the first to second year of life.