An Item Response Theory Analysis of the “Reading the Mind in the Eyes Test” in an Argentine Sample

Abstract In the field of affective neuroscience, the “Reading the Mind in the Eyes Test” (RMET) is regarded as the gold standard for assessing Theory of Mind (ToM) in general and clinical populations. Despite its widespread use and acceptance, there has been no comprehensive evaluation of the psychometric properties of the Spanish version of the test, particularly concerning its internal structure and dimensionality, especially with regard to the application of Item Response Theory (IRT). Therefore, the aim of this study is to examine the items of the Argentine version of the RMET through an IRT approach to explore its effectiveness in measuring ToM in neurotypical adult populations within Argentina. A sample of 899 adults from Buenos Aires, Argentina (34.3% men, 65.7% women) aged between 18 and 82 (M = 32.95, SD = 13.35) completed a sociodemographic questionnaire and the RMET. Based on a preliminary assessment of the data’s suitability for factor analysis, including inspection of item-level sampling adequacy, we analysed a reduced 13-item version of the test. While these items were consistent with a unidimensional structure, the main factor explained only 21.2% of the variance, and the factor loadings were relatively low. The analysis revealed weak and questionable evidence for the dimensionality of the construct, with retained items showing medium-low difficulty and moderate discrimination. Additionally, the overall reliability estimates were insufficient. Therefore, the results of this study do not support the psychometric properties of the argentine version of RMET and contribute to increasing awareness of the critical need to thoroughly evaluate its validity and reliability.