An observational measure of children's behavioural style: Evidence supporting a multi-method approach to studying temperament

This study demonstrates the potential utility of the Behavioural Style Observational System (BSOS) as a new observational measure of children's behavioural style. The BSOS is an objective, short and easy to use measure that can be readily adapted to a variety of home and laboratory situations. In the present study, 160 mother–child dyads from the Concordia Longitudinal Risk Project (CLRP) were observed during an 11-min behavioural sample. Videotaped interactions were coded using the BSOS for children's mood, activity level, vocal reactivity, approach to toys, mood consistency and adaptability. Comparisons between the BSOS observational ratings and mothers' ratings of the child on the EAS Temperament Survey (EAS) provided support for modest congruence between these two measurement systems, and revealed a differential predictive pattern of children's functioning. Specifically, the observation-based BSOS predicted children's cognitive performance and adaptive behaviour during testing, whereas the mother-rated EAS predicted maternal ratings of children's internalizing and externalizing behaviour problems. Both measures were found to independently predict mothers' ratings of parenting stress. Overall, the findings imply that neither observational measures nor maternal ratings alone are sufficient to understand children's behavioural style, and that comprehensive evaluations of children's temperament should optimally include both types of measures. Copyright © 2004 John Wiley & Sons, Ltd.