Measuring Facial Appearance in GLP-1 Agonist Use with the FACE-Q Aesthetics Item Library

Abstract Background A patient-reported outcome measure (PROM) is needed to study facial appearance in the context of rapid weight loss following use of anti-obesity medications. Such treatments can cause sunken cheeks, hollow eyes, saggy skin and an aged appearance (e.g., Ozempic face). FACE-Q Aesthetics item library can be used to create short-form fit-for-purpose scales. Objectives To create a short-form FACE-Q scale and to examine its psychometric performance in the context of anti-obesity medication use. Methods An international sample (i.e., Prolific Academic) was surveyed 3 times (initial, test-retest, 3-month follow-up). The sample included individuals who wanted to have, were having, or previously used a GLP-1 agonist to lose weight. Participants completed the FACE-Q item library that measures satisfaction with facial appearance. Rasch Measurement Theory analysis was used to item-reduce to produce a short-form scale. Psychometric properties were examined including hypothesis-based construct validity, responsiveness and test-retest (TRT) reliability. Distribution- and anchor-based minimally important differences (MIDs) were computed. Results The sample included 632 individuals who wanted to have (30.9%), were having (50.6%), or previously had (18.5%) a GLP-1 agonist to lose weight. Data for a 15-item short-form scale fit the Rasch model (χ2=130.1, df=135, p=0.60). Reliability was >0.83 for 3 reliability coefficients. Hypothesis-based construct validity was supported with 14/14 (100%) and 7/9 (77.8%) of initial and change score hypotheses confirmed respectively. The MIDs for the new scale for improvements were 6 (distribution-based) and 10 (anchor-based) points. Conclusions This FACE-Q Aesthetics short-form scale demonstrated strong measurement properties in the context of GLP-1 agonist use for weight loss.