A psychometric evaluation of the Behavioral Inhibition Questionnaire in a non-clinical sample of Dutch children and adolescents

The Behavioral Inhibition Questionnaire (BIQ) is a parent-rating scale for measuring temperamental characteristics referring to shyness, fearfulness, and withdrawal in young, preschool children. The present study evaluated the psychometric properties of the BIQ in a Dutch community sample of children with a broad age range. For this purpose, the reliability and validity of the BIQ was evaluated in three age groups: 4-7-year-olds, 8-11-year-olds, and 12-15-year-olds. The results indicated that the internal consistency of most BIQ scales was satisfactory in all three age groups. Principal component analysis of the BIQ yielded a six-factor model that was largely in keeping with the hypothesized structure consisting of the social and non-social components of behavioral inhibition. Confirmatory factor analysis indicated that this model provided a reasonable fit for the data. Further, support for the validity of the measure was obtained in all age groups. That is, BIQ scores were positively correlated with a wide range of anxiety symptoms, although the most substantial links were found for symptoms of social anxiety. Finally, a self-report version of the BIQ, which was administered to children aged 9 years and above, was found to possess good internal consistency and adequate parent-child agreement. Altogether, the results of this study indicate that suggests that the BIQ might be a reliable and valid measure for assessing behavioral inhibition not only in preschoolers but also in older children and adolescents.