Positive and negative partner relationship quality and mental health: Ambivalent and indifferent partner relationships.

Both ambivalent (high positive and negative quality) and indifferent (low positive and negative quality) partner relationships are associated with poor health. It is not known why ambivalence is health predictive in some studies and indifference in others. Measurement selection could be an explanation, with support-seeking measures linked to ambivalence and overall positive and negative relationship quality measures to indifference. No research has tested whether measurement selection affects the positive-by-negative relationship quality interaction pattern associated with health. Our purpose is to determine whether associations between the positive-by-negative quality interaction term and mental health varies depending on the relationship quality measure used, holding sample, measurement timing and relationship (partner) constant. Participants (N = 238) reported on partner relationship quality (help and distress during support-seeking, overall support, overall conflict), mental health (anxiety and depressive symptoms) and covariates. Linear regression models tested associations between positive and negative relationship qualities, their interaction and mental health, controlling for covariates. For the support-seeking measure, a positive-by-negative interaction emerged, b = 0.539, SE = 0.254, p = .035, such that when negative quality (distress) was high, higher positive quality (helpful) predicted higher anxiety. This is consistent with ambivalence. In contrast, for the broader measures, a positive-by-negative interaction also emerged, b = 0.569, SE = 0.257, p = .028, such that when negative quality (conflict) was low, lower positive quality (support) predicted higher anxiety. This is consistent with indifference. Measurement selection could affect how positive and negative relationship quality interacts to predict health, potentially accounting for why both ambivalence and indifference are associated with poor health despite being opposite relationship quality patterns.