Translation and Validation of the Functionality Satisfaction and the Functionality Intent Scales in a French Sample.

Body functionality is a promising target for the promotion of positive body image. However, research on body functionality in French-language contexts is currently limited due to the lack of validated assessment tools. This study aims to translate and evaluate the psychometric properties of the French versions of the Functionality Satisfaction Scale (FSS) and the Functionality Intent Scale (FIS). Exploratory factor analyses were conducted in a sample of 528 French adults (study 1), revealing a two-factor structure for both the FSS and FIS. Participants also completed validated measures of positive body image (functionality appreciation, body appreciation, and body esteem). A subsample (n = 150) completed the FSS and FIS again, three weeks later. Results supported convergent and divergent validity, good internal consistency, and satisfactory test-retest reliability. A second sample of 272 French adults was recruited for confirmatory factor analyses (study 2). Results confirmed the eight-item, two-factor solution for the FSS. However, support was found for a unidimensional structure of the FIS, which was ultimately retained as a four-item, one-factor scale. Measurement invariance analyses supported gender and age invariance up to the scalar level, but not at the strict level, for the FSS. The FIS also showed configural, metric, and scalar invariance across gender, whereas the scale was invariant across age only up to the metric level. This study provides support for the FSS as a useful tool for research focused on body functionality in French populations. Although the FIS demonstrated promising psychometric properties, it still requires further independent cross-validation to confirm its unidimensional structure.