Psychometric properties and measurement invariance of the Perth Alexithymia Questionnaire Short Form (PAQ-S) in Arabic, English, Italian, Spanish, Turkish, and Ukrainian.

Alexithymia is a personality trait with significant clinical impact worldwide. It is a relevant transdiagnostic risk factor for a wide range of psychopathologies, including depression, anxiety, eating and substance use disorders, and other psychosomatic conditions. This underscores the importance of having validated instruments to measure alexithymia, particularly brief scales suitable for quick and practical applications. The Perth Alexithymia Questionnaire (PAQ-S) has shown promising results in this context. However, few cross-cultural studies have validated its use, which is the aim of the present study. To this end, a sample of 2535 university students was recruited (mean age = 20.59 years; SD = 2.04; 26.75% males and 73.25% females) from Spain (n = 388), Italy (n = 376), Lebanon (n = 487), Nigeria (n = 561), Türkiye (n = 410), and Ukraine (n = 313). The PAQ-S and the Type D Personality Scale (DS-14) - designed to assess Negative Affectivity (NA) and Social Inhibition (SI) - were administered. The Classical Test Theory (CTT) and Network Analysis (NwA) were applied. The confirmatory factor analysis yielded satisfactory results in all cases, with an adequate internal consistency. Metric invariance was obtained between genders and cultures. Additionally, several of the analysed countries presented strict invariance. Therefore, the data obtained in these countries can be compared and their results extrapolated between them. The NwA supports the data obtained through the CTT, as well as the independence of alexithymia, NA, and SI constructs. Hence, the scale proved to be useful for its intended aim and may be useful to monitor alexithymia in large-scale health campaigns.