To put asunder: Are there perils of partialing in actor-partner interdependence models?

In research on couples, statistical adjustment (i.e., partialing) for correlations between partners' parallel scores is common and useful, as in the actor-partner interdependence model. Original and partialed scores are typically interpreted as assessing the same construct, but this may not be a valid assumption. Other approaches to nonindependence-such as common fate modeling-may better represent some couple constructs. This study of 300 couples utilized participants' interpersonal circumplex ratings of partners' typical behavior during marital interactions to evaluate the interpersonal meaning of unadjusted and partialed forms of the Marital Adjustment Test (MAT), a measure of overall relationship quality, and the Quality of Relationships Inventory-Support (QRI-S) and Conflict (QRI-C) scales, which measured perceived support from and conflict with the partner. After partialing partners' scores, MAT and QRI-S scores were substantially less closely associated with ratings of partners' warmth, their primary expected interpersonal correlates. Partner-partialed QRI-C scores were substantially less closely correlated with ratings of partners' hostility and were associated with a somewhat more controlling form of hostility. In contrast, partialing partners' trait optimism scores resulted in minimal changes in interpersonal correlates of this personality characteristic. Couple-level MAT, QRI-S, and QRI-C variables representing overlapping variance across partners while partialing unshared variance in spouses' scores (i.e., common fate scores) had highly similar interpersonal correlates when compared to unadjusted versions. Potential alterations in construct validity resulting from partialing partners' scores warrant interpretive caution, and alternative analytic frameworks (e.g., the common fate model) may better maintain the construct validity of some dyadic measures. (PsycInfo Database Record (c) 2022 APA, all rights reserved).