Are changes in marital satisfaction sustained and steady, or sporadic and dramatic?

Area of Science:

• Psychology
• Sociology
• Family Studies

Background:

• Prominent relationship theories suggest fluctuating closeness, yet longitudinal studies often show stable or declining satisfaction.
• Group-based trajectory models (GBTMs) reinforce this view but overlook individual differences and within-person variability.

Purpose of the Study:

• To investigate if growth mixture models (GMMs) provide a more accurate characterization of couples' satisfaction changes over time.
• To determine if accounting for within-class individual differences and within-person variability alters established models of relationship satisfaction.

Main Methods:

• Longitudinal data from 12 independent studies of first-married couples (N = 1,249) were analyzed.
• Growth mixture models (GMMs) were employed, allowing for class-specific individual differences and within-person variability.
• GMMs were compared to group-based trajectory models (GBTMs) that constrained these variances.

Main Results:

• GMMs provided a better fit to the data than GBTMs.
• Significant within-person variability in satisfaction was observed within each identified class.
• Marital dissolution was strongly associated with classes exhibiting greater satisfaction volatility (3.8-5.7 times more likely).

Conclusions:

• Couples' satisfaction exhibits considerable within-person fluctuations, aligning with theoretical expectations of relationship dynamics.
• The volatility of satisfaction, particularly in early marriage, is a crucial factor in marital stability and dissolution.
• Time-varying factors influencing satisfaction fluctuations are critical for understanding marital success and failure.