Psychometric properties of an Arabic translation of the short 9-item drive for muscularity scale (DMS-9).

Background: After the original 15-item Drive for Muscularity Scale developed by McCreary et al. in 2004, a more theoretically based scale that replicates the original DMS subscales with a better conceptual clarity and a shorter number of items, i.e., the DMS-9, has recently been developed by Chaba et al. in 2018. We sought to contribute to the literature especially under the Arab context, by investigating the psychometric properties of an Arabic translation of the DMS-9 in a sample of Arabic-speaking Lebanese university students of both genders.

Methods: University students (N = 402; 55.2% females) from multiple universities in Lebanon were invited to fill the survey in this cross-sectional designed study (December 2022 and January 2023). Our sample was chosen using the snowball technique; a soft copy of the questionnaire was created using google forms software, and an online approach was conceived to proceed with the data collection.

Results: Using an Exploratory Factor Analysis-to- Confirmatory Factor Analysis strategy, we found that the original two-factor model of the DMS proposed in the parent study was adequately replicated in our sample. The two DMS-9 factor scores showed very good McDonald's omega values (ω > 0.8). Findings also showed that gender invariance was achieved at the configural, metric, and scalar levels. Additionally, drive for muscularity scores correlated in the expected way with other study variables, providing support for the convergent and divergent validity of the Arabic DMS-9. Specifically, we found that greater drive for muscularity attitudes and behaviors significantly correlated with more severe muscle dysmorphic symptoms, inappropriate eating attitudes, muscle bias internalization, and lower body appreciation.

Conclusion: Findings preliminarily suggest that the Arabic DMS-9 is psychometrically sound and suitable tool to assess the drive for muscularity construct among Arabic-speaking community adults. Making the Arabic DMS-9 available will hopefully benefit the scientific community working in Arab settings, promote local and international research in this area, and offer descriptive data on how drive for muscularity may interfere with health indicators in the general Arab population.