Sequential progressions in a theory-of-mind scale: longitudinal perspectives.

Consecutive retestings of 92 U.S. preschoolers (n=30), Chinese preschoolers (n=31), and deaf children (n=31) examined whether the sequences of development apparent in cross-sectional results with a theory-of-mind scale also appeared in longitudinal assessment. Longitudinal data confirmed that theory-of-mind progressions apparent in cross-sectional scaling data also characterized longitudinal sequences of understanding for individual children. The match between cross-sectional and longitudinal sequences appeared for children who exhibit different progressions across cultures (United States vs. China) and for children with substantial delays (deaf children of hearing parents). Moreover, greater scale distances reflected larger longitudinal age differences.