Measuring Need-Supportive and Need-Thwarting Behaviors Among Athletes from Different Sports: Scale Validity and Reliability

The objective of the present research is to examine the factor structure of the Interpersonal Behavior Questionnaire (IBQ) and the Interpersonal Behavior Self Questionnaire (IBQ-Self) in the sport context. Confirmatory factor analyses were used to assess the psychometric properties and measurement invariance across sex and sports. For the IBQ, a sample of 813 Portuguese athletes aged between 15 and 32 years (M = 23.46; SD = 4.92) took part in this study. They had an average sports experience of approximately 7.62 +/- 3.23 years. For the IBQ-Self, a sample of 606 Portuguese coaches aged between 20 and 73 years (M = 34.43; SD = 11.56) participated in this study. Both scales demonstrated good fit, achieved convergent and discriminant validity, exhibited acceptable internal consistency, and demonstrated invariance across sex and sports. Regarding the analysis of psychometric properties, the IBQ and IBQ-Self can be applied to Portuguese athletes and their coaches to measure perceived behaviors of others and self-reported behaviors.