Abstract
This research consists of two studies which aimed to: (1) evaluate the psychometric properties of a new self-report measure for the assessment of mentalizing, the Multidimensional Mentalizing Questionnaire (MMQ); and (2) investigate the ability of the instrument to discriminate between community and clinical populations. A sample of 349 participants (19% male, 81% female; M(age) = 38.6, SD = 15.3) filled in the MMQ and other self-report measures, in order to assess the factor structure, reliability and some aspects of construct validity of the measure. Then, a clinical sample (N = 46; 52% male and 48% female; M(age) = 33.33, SD = 12.257) and a community one (N = 50; 42% male and 58% female; M(age) = 38.86, SD = 16.008) filled in the MMQ, to assess its clinical sensitivity. The factorial analysis identified six principal dimensions of the measure: reflexivity, ego-strength, relational attunement, relational discomfort, distrust, and emotional dyscontrol. The MMQ showed satisfactory psychometric properties and a theoretically relevant factor structure. Furthermore, significantly greater impairment in mentalizing was found in the clinical sample in respect of the community one. The findings are discussed in terms of clinical implications, emphasizing the usefulness of the MMQ in both research and clinical practice.