Kito, M. (鬼頭美江) (2016). 
Shared and unique prototype features of relationship quality concepts. 
対人関係の良好さに関連する概念間で共通するプロトタイプ特徴と概念特有のプロトタイプ特徴
Personal Relationships, 23, 759-786. 
doi: 10.1111/pere.12156

Previous research on relationship quality concepts suggests they are not as distinct as expected. What aspects are similar and distinct across these concepts? Using a prototype approach, this research identified the commonalities and uniqueness of 7 relationship quality concepts: commitment, intimacy, love, passion, satisfaction, trust, and relationship quality. The results indicated that (a) 4 features were shared across all 7 concepts, and some were exclusive to each concept, and (b) shared features were rated as more important for romantic relationship functioning than unique features both explicitly and implicitly. This research provides a framework to understand overarching and distinct aspects of relationship quality concepts and how this is reflected in people’s evaluation of what is important in romantic relationships.