Measuring Children’s Exposure to Interparental Hostility: The Psychometric Properties of the O’Leary–Porter Scale in Three Countries

Abstract Purpose Parental conflict is a well-established risk factor for children’s emotional and behavioral adjustment. Consequently, psychometrically valid tools are required to assess the frequency and type of interparental conflict. The O’Leary-Porter Scale (OPS) is a 10-item caregiver-report measure of overt hostility displayed in front of children. While commonly used, the OPS’s construct validity is not extensively tested outside the United States. The present study evaluated the psychometric properties and measurement invariance of the OPS as part of a multi-country parenting program. Methods Caregivers ( n = 752) of children aged 2 to 9 completed the OPS in North Macedonia, Moldova, and Romania. Convergent validity was evaluated through correlations with measures of caregiver distress, parenting stress, couple satisfaction, and positive parenting. Confirmatory factor analysis (CFA) tested a unidimensional structure in each country, followed by multi-group CFA and differential item functioning (DIF) analysis. Results The original model showed marginal to acceptable fit. Item 10 (reverse‑scored “display affection”) was removed due to low or negative loadings and correlating one item pair improved model fit. Loadings for the final 9-item model were moderate to strong with good internal consistency. Metric invariance was established. Convergent validity showed consistent but variable effects. Conclusion This is the first multi-country validation of the OPS in over four decades, extending evidence beyond U.S. samples. The OPS shows viability as a tool for measuring children’s exposure to interparental hostility in comparable contexts, and item-level recommendations discussed herein may contribute to refining the scale and improving its applicability in future research.