Misophonia, a disorder characterised by an extreme sensitivity to certain sounds, is increasingly being studied in cross-cultural settings. The S-Five scale is a multidimensional psychometric tool initially developed to measure the severity of misophonia in English-speaking populations. The scale has been validated in several languages, and the present study aimed to validate the European Portuguese S-Five scale in a Portuguese-speaking sample. The scale was translated into Portuguese using a forward-backwards translation method. The psychometric properties of the S-Five scale were evaluated in a sample of 491 Portuguese-speaking adults. Confirmatory factor analysis supported a five-factor structure consistent with previous versions of the S-Five scale. The five factors were: (1) internalising appraisals, (2) externalising appraisals, (3) perceived threat and avoidance behaviour, (4) outbursts, and (5) impact on functioning. The satisfactory psychometric properties of the S-Five scale further indicated its cross-cultural stability. As a psychometrically robust tool, the S-Five can measure misophonia in Portuguese-speaking populations, allowing future studies to explore and compare misophonia in this population.Misophonia, a disorder characterised by an extreme sensitivity to certain sounds, is increasingly being studied in cross-cultural settings. The S-Five scale is a multidimensional psychometric tool initially developed to measure the severity of misophonia in English-speaking populations. The scale has been validated in several languages, and the present study aimed to validate the European Portuguese S-Five scale in a Portuguese-speaking sample.

Participants were recruited through online social media groups, mailing lists, adverts and contacts. and this type of convenience sampling allowed for sampling to be carried out quickly and at a low cost. The consent of participants was collected before the completion of survey measures, with the provision of an information sheet. The inclusion criteria set for participation in the study were being at least 18 years old and fluent in Portuguese. The exclusion of those diagnosed with a severe learning or intellectual disability, to the extent that participating in a self-report survey was impossible, was set as a criterion. Demographic information from participants was collected, including age, gender, ethnicity, education level, occupation, country of birth and country of residence. The survey asked respondents to report the formal diagnoses of mental health conditions, audiological conditions, and neurodevelopmental conditions, whether they knew the term misophonia and if they identified with misophonia. Several self-report questionnaires were included. The S-Five, Amsterdam Misophonia Questionnaire-Revised, Misophonia Questionnaire, Patient Health Questionnaire-9, Generalised Anxiety Disorder-7 scale, and Anxiety Sensitivity Index-3.