Couples' self-control and marital conflict: Does similarity, complementarity, or totality matter more?

Research that approached self-control as a dyad-level predictor of relationship outcomes is hitherto scarce. To address this research gap, this study investigates three configurations of couples' level of self-control on marital conflict. We test three competing hypotheses suggested in the literature: similarity hypothesis, complementarity hypothesis, and totality hypothesis. The data used to test these hypotheses is a unique couple data (N = 1698 individuals from 894 married couples) of husbands and wives from a representative sample in Hong Kong. Two-level random-intercept models were employed. Based on our analysis with the difference-score method and response surface analysis, we find evidence to support the similarity hypothesis. The similarity of self-control between husband and wife is important in predicting marital conflict. In contrast, the total level of self-control is not predictive of marital conflict. This study highlights that marital conflict is strongly associated with the mismatch of self-control between partners.