Taking stock of the longitudinal study of romantic couple relationships: The last 20 years

Longitudinal dyadic research provides significant benefits for our understanding of romantic couple relationships. In this systematic review, we begin by providing a broad overview of topical trends and approaches in longitudinal couple relationships research from 2002 through 2021. Then, we narrow our review to dyadic relationship quality articles, highlighting key themes as well as noting important gaps in the research. Using an intersectional perspective that acknowledges multiple ways that disadvantage, power, and oppression may be seen in both research and in couples' lived experience, we note prominent paradigms used in examining couple relationships, what types of questions have been most valued, and what groups and approaches are underrepresented in the literature. Most longitudinal couple relationships research is quantitative, relies on self-report approaches from American couples in the early-to-middle years of their relationships, concentrates more on negative aspects of relationships than positives, and takes a communication-satisfaction paradigm in studying couples. We see a clear need to increase the use of methodologies beyond self-report measures, conduct more studies with within-group minority, older adult, culturally-diverse, and context-specific samples to explore the diversity of relationships, and fully consider both strengths and positive processes in relationships as well as the challenges couples experience.