An exploratory factor analysis (EFA) on the five items related to children’s perceptions of parental relationship discord was conducted to inform the calculation of the parental relationship discord composite. After establishing unidimensional factor structure (see Supplementary Information and Supplementary Tables 1 and 2), a composite measure was calculated by taking the prorated sum of the items for participants who responded to at least 3 items. Binary items were coded 0 or 1. Four-response ordinal items were rescaled to range between 0 and 1 (0, 0.33, 0.66, 1) so that ordinal and binary items were weighted similarly in the prorated sum.
