The Psychometric Properties of The Subjective Vitality and Depletion Scale (Svds) In A Sample of Older Adults: A Dual-Country Study

Abstract

Recent projections estimate that the global population of older adults will reach 1.4 billion by 2030 and 2.1 billion by 2050 (WHO, 2022). Loss of energy and fatigue are common complaints in later life, diminishing well-being and quality of life. Self-Determination Theory (SDT) has recently proposed a new model, based on two related, yet distinct constructs, Subjective Vitality and Depletion. This model can provide a better understanding of older adults' energy dynamics. The aim of the present study is to validate the Subjective Vitality/Depletion Scale (SVDS), a new tool for the assessment of this model, on a sample of 726 older adults (51.1% females; age range = 65 - 95 years; M_age = 72.57, SD_age = 6.49) from the USA and Italy. Participants completed the SVDS along with measures of personality, general physical and psychological health, and physical activity.

Confirmatory factor analysis of the SVDS supports the SDT model, indicating that Subjective Vitality and Subjective Depletion are distinct yet related constructs. Full measurement invariance for the scale was achieved across gender and age subgroups, while partial scalar invariance was established across different countries. Correlations with personality, general physical and psychological health, and physical activity support the SVDS convergent, discriminant, and nomological validity.

Overall, the study provides evidence that the SVDS is a valid and reliable tool for assessing Subjective Vitality and Depletion in older adults within the SDT framework, showing consistency in construct conceptualization and interpretation across groups with diverse characteristics and cultural backgrounds.