Italian Adaptation and Validation of the Sibling Attachment Inventory

Objective This study aims to adapt and validate the Sibling Attachment Inventory (SAI) to the Italian context and to examine its psychometric properties. Method Using an Internet-based survey, data were collected from 500 Italian young adults (ages 18-30). Exploratory and confirmatory factor analyses were carried out to explore the factorial structure of the SAI. Correlations with the Inventory of Parent and Peer Attachment (IPPA), the Lifespan Sibling Relationship Scale, the Satisfaction with Life Scale, and the Rosenberg Self-esteem Scale were carried out to verify convergent and predictive validity. Results Results indicated the instrument had good levels of internal consistency and a mono-dimensional structure, also providing evidence for validity. By comparing three models proposed in the literature, results indicated that the 3-factor model had the best fit indices. Results also indicated that secure attachments were linked to high levels of self-esteem and satisfaction with life. Conclusion The Italian version of the SAI has good psychometric properties, suggesting its ability to assess young adults’ sibling attachment in the Italian cultural context and it is expected to be a useful self-report measure in research aimed to study individual differences in young adults’ sibling attachment.