Psychometric Validation of the Weight and Emotions Scale (WES) in Adults with Obesity or Overweight

Individuals with obesity or overweight experience a substantial socioemotional burden and lower quality of life. Existing patient-reported outcome (PRO) instruments do not adequately measure emotional functioning concepts important to individuals with obesity/overweight. This study describes the psychometric properties of the Weight and Emotions Scale (WES), a new PRO measure to evaluate emotional functioning in adults with obesity or overweight.

120 adults completed two web-based surveys (baseline, week 2). Survey 1 comprised the 16-item WES, Control of Eating Questionnaire, Impact of Weight on Quality of Life-Lite Clinical Trials Version, Impact of Weight on Self-Perceptions Questionnaire, and Patient Global Impression of Severity (PGIS) 'Overall Emotional Impact of Weight.' Survey 2 included the WES and PGIS 'Overall Emotional Impact of Weight.' Factor structure, reliability, and validity of the WES were assessed.

Exploratory factor analysis of the WES supported a two-factor structure as items loaded strongly (≥ 0.59) on factors corresponding to positive and negative feelings. The unidimensional framework was revised to include two WES domains ('Positive Feelings' [8 items] and 'Negative Feelings' [8 items]). The WES domain and total scores demonstrated excellent internal consistency (Cronbach's alpha ≥ 0.90) and good test-retest reliability (intraclass correlation coefficient: 0.87-0.89). Convergent validity of the WES was demonstrated via large correlations with the Impact of Weight on Quality of Life-Lite Clinical Trials Version 'Psychosocial' score and items, Impact of Weight on Self-Perceptions Questionnaire total score, and PGIS 'Overall Emotional Impact of Weight.' Known-groups validity was demonstrated via higher WES domain and total scores in participants who reported feeling good about their weight (PGIS 'Overall Emotional Impact of Weight').

The final version of the WES with 16 items is a reliable and valid PRO measure for assessing emotional functioning in individuals with obesity or overweight, with potential utility in observational studies, clinical trials, and clinical practice.