Intervening to Strengthen Intimate Relationships: Moderators and Mediators in Three Randomized Controlled Trials

Although intimate relationships are a rewarding experience for many, others struggle to maintain healthy and lasting partnerships. This is especially true of couples living with low-incomes, who experience adverse relationship outcomes, such as divorce and dissatisfaction, at a disproportionate rate. Despite the need for effective interventions to prevent negative outcomes for lower-income couples and their families, the existing literature is equivocal on the most effective ways to intervene. Using data taken from three randomized controlled trials, the three studies in this dissertation project serve to test existing models of intervention, focusing on enhancing our knowledge of how these interventions operate and for whom they work best. Study 1 examines whether intervention effects vary systematically as a function of risk in three theoretically distinct preventive programs. Results indicate that treatment effects varied as a function of risk, and more so with variables capturing relational risk factors than individual risk factors. High-risk couples (e.g., couples with lower levels of baseline commitment and satisfaction) tended to decline less rapidly in satisfaction than low-risk couples following treatment. Study 2 examines whether intervention effects on relationship satisfaction are mediated by observational assessments of relationship communication and whether any such effects are moderated by couples’ pretreatment risk. Results indicate that couples who received the intervention reported higher average satisfaction at 30 months than control couples, regardless of their level of pretreatment risk, but only higher risk couples experienced an improvement in observed communication. Contrary to prediction, treatment effects on satisfaction were not mediated by improvements in communication. Finally, Study 3 examines the effects of job-related and school-related interventions on 3-year marriage rates, and whether relational or financial factors mediate this effect. Results indicate that marriage rates decreased, from 17% to 10%, among couples in which men participated in school-related interventions. Mediation analyses indicate that school-related interventions reduce the amount of time men spend with their child and the amount of money they contribute to their household, reducing marriage rates in turn. Together, these studies help refine our understanding of how to best improve relationship outcomes through preventive programs