Does Marital Duration Moderate (Dis)Similarity Effects of Personality on Marital Satisfaction?

This study examined the actor, partner, and (dis)similarity effects of personality on marital satisfaction, considering the interaction with marital duration. Participants were 749 Japanese married couples. The results of an actor–partner interdependence model, which includes interaction with marital duration, showed that there was little interaction between actor and partner effects and marital duration, indicating that both one’s own and the partner’s personality have consistent effects on satisfaction throughout marital duration. In contrast, similarity effects did interact with marital duration. In shorter marital duration, similar couples were less satisfied, whereas similarity had no effect on satisfaction in longer marital duration. We discuss the possible influence of the transition from a romantic relationship to a marital relationship.