Psychometric properties of the Functional Appreciation Scale (FAS) in middle-aged and older adults in Mexico

Abstract

The aging process involves a series of physical changes that accelerate after age 50, as functional decline is believed to begin early, marking the physical limitations that socially characterize old age. Body image therefore has a clear influence on the perception of vitality in both middle age and old age. Consequently, the study of body image from age 50 onward has been significant in relation to anxiety, depression, and physical changes; thus, the objective of the present study is to determine the psychometric properties of the Functional Appreciation Scale in middle-aged and older Mexican adults. A total of 357 participants were recruited, divided into two subsamples, and asked to complete a battery of tests that included the target scale and measures of self-esteem, gratitude, and body appreciation. All assessments were conducted individually and face-to-face. Among the main results, both exploratory and confirmatory factor analyses supported the scale’s one-dimensionality. Furthermore, the FAS showed invariance between men and women, indicating that the construct structure and the perception of functionality behave similarly regardless of gender. Additionally, associations were observed between the Functional Appreciation Scale and body appreciation, gratitude, and self-esteem. The results are discussed in the context of previous applications, particularly in studies that sought to validate the instrument among older adults.