研究業績

Objective: To identify longitudinal patterns of postdivorce coparenting in Japan by simultaneously examining conflictual and cooperative dimensions over 2 years. Background: Despite the multidimensional nature of coparenting, longitudinal research in East Asian contexts remains scarce. Examining how conflict and cooperation jointly develop may clarify postdivorce family reorganization in a non‐Western context. Methods: A sample of 500 Japanese mothers who had divorced within the past 2 years and were living with children aged 2–17 years participated in a 2‐year, nine‐wave study. Parallel‐process latent class growth analysis identified longitudinal patterns, and a three‐step approach examined predictors of class membership. Results: Three patterns emerged: Conflictual (26.9%), Cooperative (29.0%), and Disengaged (44.2%). The Disengaged group showed low levels of both conflictual and cooperative coparenting, whereas the Conflictual group showed higher initial conflict and was associated with greater predivorce paternal aggression toward children. Conclusion: Postdivorce coparenting in Japan showed distinct longitudinal patterns, with low conflict and cooperation being most common. The findings highlight the value of examining both dimensions simultaneously. Implications: Practitioners should provide differentiated, safety‐sensitive support reflecting families' relational structures, with careful assessment of conflict, safety concerns, and family circumstances.