A population-based sample of Norwegian children aged 18 months
(N=921), 30 months
(N=784), and 50 months (N=737) was examined with the
EAS Temperament Survey
(Buss & Plomin, 1984). The factor structure, psychometric properties,
and stability estimates
of the instrument were assessed. A cross-validation of the temperament
factors of
Emotionality, Activity, and Shyness show that the covariance structure
conforms with the
three scales described by Rowe and Plomin (1977) and Boer and Westenberg
(1994). When
items from the experimental scale of Sociability were included in the analysis,
a four-factor
solution confirmed the separate usability of this scale as well. The factor
structure does not
seem to vary substantially with the age of the children. The scores on
the four temperament
scales show high stability from one time of measurement to the next. Although
no strong
gender differences were found, there were significant age trends. Emotionality
and Shyness
increased from 18 to 50 months, while Activity and Sociability decreased.
The study
confirmed the structure and stability of the EAS over 3 years among young
children,
providing support for its use with children as young as 18 months.