Development of Sibling Rivalry Instrument on Adolescents

This study aims to develop a measurement instrument for sibling rivalry that has been previously constructed. Previous research indicated a unidimensional model, but this study found a more suitable multidimensional model with three dimensions: jealousy, resentment, and competition. Through the confirmatory factor analysis (CFA) method, the instrument underwent modification, resulting in a final 8-item instrument divided into two items for jealousy, three for resentment, and three for competition. The CFA analysis showed that the instrument has good overall validity and meets convergent and discriminant validity criteria. The instrument’s reliability is also considered good. Thus, this instrument can effectively measure sibling rivalry in adolescent populations.