Kito, M. (鬼頭美江) (2016). 
Shared and unique prototype features of relationship quality concepts. 
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.