The Infidelity Scale: Psychometric properties and gender invariance among Portuguese adults

La Escala de Infidelidad: propiedades psicométricas e invariancia de género en adultos portugueses

Telma Catarina Almeida , Filipa Fernandes

Suma Psicológica, (2022), 29(2), pp. 110-118.

Received 25 March 2022
Accepted 8 July 2022


Introducción: La infidelidad es una ruptura de la confianza que influye en las relaciones íntimas. Se puede dividir en infidelidad sexual o emocional. En Portugal, hay pocos estudios sobre este tema con medidas adecuadas. Objetivo: Esta investigación tiene como objetivo analizar la estructura factorial, las propiedades psicométricas y la invariancia de género de la Escala de Infidelidad (IS) entre adultos portugueses. Método: Se aplicó el protocolo de investigación a 660 adultos portugueses (455 mujeres y 205 hombres) de entre 18 y 79 años que fueron infieles en sus relaciones. Resultados: El análisis confirmatorio mostró una estructura con dos factores (infidelidad física y emocional), y se encontraron buenos valores de validez convergente y discriminante. Los resultados mostraron un ajuste satisfactorio del modelo y la no invariabilidad de la estructura factorial entre mujeres y hombres. Conclusión: Esta es la primera versión en portugués de la IS, como medida que permite estudiar las relaciones íntimas, contribuyendo para el desarrollo de la investigación multicultural.

Palabras clave:
Escala de Infidelidad, relación íntima, evaluación, género


Introduction: Infidelity is a breach of trust or a crossing of the boundaries of the primary relationship and it influences intimate relationships. It can be categorised as either sexual or emotional infidelity. In Portugal, there have been few studies on this subject using suitable instruments. Objective: This study aimed to analyse the factor structure, psychometric properties, and gender invariance of the Infidelity Scale (IS) in Portuguese adults. Method: The sample comprised 660 Portuguese adults (455 women and 205 men) between 18 and 79 years of age who had been unfaithful in their relationships. Results: The confirmatory analysis showed a structure with two factors (sexual and emotional infidelity), and good values for convergent and discriminant validity were found. The results displayed a satisfactory model fit and the non-invariance of the factor structure between women and men. Conclusion: This is the first Portuguese version of the IS, an instrument for the study of intimate relationships which contributes to the development of multicultural research.

Infidelity Scale, relationship, assessment, gender

Artículo Completo

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