Continuity of temperament from infancy to middle childhood.

Continuity of temperament from 6 months (the IBQ) to 5.5 years (the CBQ) was explored in Finnish children (n=231) within the theoretical framework deviced by Rothbart. Activity level, smiling and laughter, distress to limitations and fear showed significant differential homotypic and heterotypic continuity, while soothability and duration of orienting showed significant differential heterotypic continuity. On the level of latent superconstructs, infant positive and negative affectivity accounted for 4.6, 22.3, and 6.0% of the variance in childhood extraversion, effortful control and negative affectivity, respectively. Infant and childhood temperament clustered into profile types named "resilient", "undercontrolled", and "overcontrolled" mirroring ipsative continuity. These findings give empirical credence to Rothbart's theory by replicating and extending previous findings in significant ways.