Development and application of the State–Trait Serenity Scale

Serenity is crucial for well-being, and should be measured from two perspectives: state and trait. However, while Trait Serenity Scales have been developed, there are no scales for state serenity. Therefore, we developed a State–Trait Serenity Scale (STSS). We first collected words related to serenity from Japanese participants. We then considered the factor structure of serenity in terms of state and traits using an exploratory factor analysis. We also confirmed the relationship between well-being and state and trait serenity. We examined the possibility of measuring psychological states after watching videos to confirm the scale’s usefulness. The State Serenity Scale had 14 items with three factors: “calmness,” “excitement,” and “richness,” and the Trait Serenity Scale had 11 items with two factors: “calmness” and “excitement.” The factors of both scales had good internal consistency. Confirmatory factor analysis showed that both the scales and factors had factor convergent and discriminant validity. The STSS showed positive correlations with well-being. Furthermore, evaluating and comparing feelings of serenity after watching video clips by genre was possible. These results suggest that trait and state positive emotions are related to well-being, and that the STSS can evaluate serenity and well-being from both perspectives.