Psychometric properties of the Arabic versions of the Three-Item Short Form of the modified Weight Bias Internalization Scale (WBIS-3) and the Muscularity Bias Internalization Scale (MBIS)

BackgroundThere is a lack of psychometrically sound measures to assess internalized weight and muscularity biases among Arabic-speaking people. To fill this gap, we sought to investigate the psychometric properties of Arabic translations of the Three-Item Short Form of the Modified Weight Bias Internalization Scale (WBIS-3) and the Muscularity Bias Internalization Scale (MBIS) in a sample of community adults.MethodsA total of 402 Lebanese citizens and residents enrolled in this cross-sectional study (mean age: 24.46 years (SD = 6.60); 55.2% females). Exploratory Factor Analysis (EFA) was conducted using the principal-axis factoring and oblimin rotation to estimate parameters and the parallel analysis to determine the number of factors. CFA was conducted using the weighted least square mean and variance adjusted estimator which was recommended for ordinal CFA.ResultsAn Exploratory Factor Analysis of the WBIS-3 resulted in a robust single-factor solution for the three items. An examination of the factorial structure of the MBIS revealed a two-factor structure, which showed adequate model fit. We obtained excellent internal consistency as indicated by McDonald's omega coefficients of .87 for the WBIS-3 total score and ranging between .92 and .95 for the MBIS two factor scores. Cross-sex invariance of the MBIS was confirmed at the configural, metric, and scalar levels. Convergent validity was supported by significant correlations between the WBIS-3 and MBIS. Divergent and concurrent validity were approved by showing small to medium correlations between MBIS/WBIS-3 scores and muscle dysmorphia, disordered eating symptoms, and body image concerns.ConclusionFindings suggest that the Arabic versions of the WBIS-3 and MBIS are suitable for use in Arabic-speaking adults. Plain English Summary Individuals with overweight or obesity frequently experience weight-based stigmatization. The widespread belief that weight is a matter of personal will and self-control results in various weight-based stereotypes (e.g., laziness, lack of self-discipline, or neglect). Furthermore, the influence model of body image identifies internalization of societal body ideals as a risk factor for developing body dissatisfaction, and subsequent disordered eating behavior. Hence, internalization of two dimensions of body image ideals, thinness and muscularity, is associated with body dissatisfaction and eating concerns. Weight Bias Internalization Scale (WBIS-3) is a shortened version of the modified version of the Weight Bias Internalization Scale (WBIS-M) designed to evaluate the weight bias internalization. As for the Muscularity Bias Internalization Scale (MBIS), it assesses the extent to which an individual endorses muscularity-based stereotypes and engages in negative self-evaluations due to muscularity. These two scales are not yet validated in Arabic. To that end, we aimed to translate and validate the Arabic version of the WBIS-3 and MBIS in the present study, which would in turn facilitate improved research and clinical practices related to weight and muscularity biases internalization in Arabic-speaking nations. The present findings provide support for the psychometric properties of the Arabic version of the WBI-3 and MBIS in examining weight and muscularity biases internalization in Arabic-speaking adults in Lebanon.