Validity and reliability of a new culturally-sensitive affect scale: The Brazilian Portuguese Affect Scale (EAPB - Escala de Afeto do Português-Brasileiro)

Objective Properly measuring affects and emotions in specific populations is crucial for advancing affective sciences research across cultures and contexts. Reliable and valid assessment tools enable researchers to measure emotional responses accurately, which is essential for testing hypotheses and developing interventions. In Brazil, affective research relies on translations rather than specifically constructed scales. To fill this gap, we developed the EAPB ( Escala de Afeto do Português-Brasileiro ) using a rigorous and up-to-date protocol for instrument construction. Here we report on the reliability and validity of the EAPB in a representative country-wide sample. Methods From a large and representative sample of 3479 participants recruited, 2896 were included. Reliability was examined using McDonald’s Omega for internal consistency and test-retest analysis for temporal stability. EAPB ’s structural validity was investigated using Exploratory and Confirmatory Factorial Analyses. Results The EAPB is a properly constructed and validated affect scale for the Brazilian population, comprising a short version (9 items) and a long version (21 items). The short version follows a 2-factor structure (Positive Affect and Negative Affect), while the long version comprises 8 affective dimensions (Sadness, Joy, Fear, Anxiety, Rage, Humiliation, Tiredness and Energy). An excellent level of internal consistency and expected moderate temporal stability were found. Conclusion The findings provide solid evidence of reliability and internal validity for the new EAPB scale. In line with open-science principles, both scale versions are publicly available and free to use.