Abstract
The Kyoto Scale of Psychological Development (KSPD), a standardized developmental assessment tool for Japanese infants, and the Bayley Scales of Infant Development second edition (BSID-II) have been widely used in clinical assessments and research on infants. The purpose of this study was to compare the psychometric indices of the KSPD with those of the BSID-II in a large sample of Japanese infants. The KSPD and BSID-II were administered to 861 7-month-old infants and to 894 18-months old infants. All of the correlation coefficients between the two scales were significant except those between the Language-Social area of the KSPD and Language, Social facets of the BSID-II at 7 months of age. The findings of this study revealed that the results of the KSPD and BSID-II were comparable. There are many reports using the KSPD in Japan, and the findings based of the KSPD and BSID-II may be shared.
