Validation of the Adult Interpersonal Acceptance-Rejection Scale to measure parents, best friend, and romantic partner acceptance in Bangladeshi young adults.

Interpersonal acceptance-rejection is one of the central determinants of well-being and optimal functioning not only for children but also for adults. The Adult Interpersonal Acceptance Rejection Scale (AIARS) is a unified scale that measures adults' current interpersonal acceptance-rejection across pivotal close relationships (mother, best friend, and romantic partner), which was originally developed in the Western culture. However, the AIARS has yet to be comprehensibly investigated. Therefore, this study aimed to adapt and validate the AIARS in a non-Western cultural context, also incorporating a new sub-scale of father acceptance. For this purpose, 616 Bangladeshi young adults (60 % women and 40 % men) aged 18-26 years (Mage = 21.63 years, SD = 1.72) were conveniently selected. Classical test theory (CTT)-based confirmatory factor analysis (CFA) confirmed a four-factor model (mother acceptance, best friend acceptance, romantic partner acceptance, and newly added father acceptance factor). The measurement invariance test provided evidence of invariance across genders. Item response theory (IRT)-based analyses indicated that all factors of the Bangla AIARS yielded substantial amounts of information across the latent continuum. The correlations with Personality Assessment Questionnaire (PAQ for assessing psychological adjustment) and Life Orientation Test-Revised (LOT-R for assessing optimism) supported the concurrent validity of the Bangla AIARS. It had excellent internal consistency at the subscale level. The newly validated Bangla AIARS is a viable and reliable instrument for measuring young adults' four pivotal interpersonal relationships.