Assessing need-supportive and need-thwarting interpersonal behaviours: The Interpersonal Behaviours Questionnaire (IBQ)

The objectives of the present studies were to design and validate the Interpersonal Behaviours Questionnaire (IBQ and IBQ-Self). The IBQ assesses perceptions of interpersonal behaviours of others according to Self-Determination Theory in the context of autonomy-supportive, competence-supportive, and relatedness-supportive behaviours, as well as autonomy-thwarting, competence-thwarting, and relatedness-thwarting behaviours, while the IBQ-Self assesses an individual's own report of these behaviours. In Study 1, participants reported on the interpersonal behaviours of people in their lives. Through a series of confirmatory factor analyses, a six-factor, 24-item scale structure was determined. Results supported the validity of the scale and correlation analyses suggested that the subscales were related to basic need satisfaction. In Study 2, the psychometric properties of the scale were re-evaluated and the scale was tested for gender invariance. The results suggested that the scale structure held and that it was invariant across genders. Finally, in Study 3, the psychometric properties of the IBQ-Self were evaluated using a student sample reporting on their behaviours when they interact with other people. The results supported that the IBQ-Self factor structure held and was invariant for men and women. Overall, the results of all three studies supported the validity of the IBQ and the IBQ-Self.