Validation of the Weight Self-Stigma Questionnaire in a Polish sample: Factor structure and measurement invariance by gender

This study aimed to confirm the factorial structure of the Polish Weight Self-Stigma Questionnaire (WSSQ) and to test structural validity, internal consistency and measurement invariance of the questionnaire across gender, Body Mass Index (BMI) and other psychological measures. The sample was recruited from the general Polish population (N=1055), age 18–55. Participants completed the WSSQ, The Yale Food Addiction Scale (YFAS 2.0), Emotional Eating and Restrained Eating subscales from The Dutch Eating Behavior Questionnaire (DEBQ), The Depression, Anxiety and Stress Scale – 21 (DASS-21) and sociodemographic survey.The Polish WSSQ showed good overlap with the original structure in the two-factor model (Self-devaluation and Fear of Enacted Stigma). Factor loadings were satisfactory and both subscales showed good internal consistency. Measurement invariance revealed gender differences in the WSSQ score. The construct validity was confirmed with strong correlations with emotional eating and food addiction. As expected, the WSSQ total score was moderately positively associated with depression and stress severity. The correlations were the weakest for retrained eating and body mass index. The Polish WSSQ is a valid and reliable tool for the assessment of weight-related self-stigma among patients with overweight/obesity. Future studies should investigate the gender differences as well as the test-retest reliability and longitudinal invariance. Finally, the sociodemographic information should be taken into account when interpreting the WSSQ results.