The BODY-Q Cellulite Scale: A Development and Validation Study

BACKGROUND: Cellulite is a localized metabolic disorder of the subcutaneous tissue. To measure the impact of cellulite and its treatment(s) on patients' health-related quality of life, a psychometrically sound patient-reported outcome measure is needed. OBJECTIVES: The authors sought to develop and field test a new BODY-Q cellulite scale to measure the appearance of cellulite. METHODS: Appearance-related codes from the original BODY-Q qualitative interviews were reexamined, and a set of cellulite-specific items was developed and refined through cognitive patient interviews (n = 10) and expert input (n = 17). This scale was field-tested in adults with cellulite through 2 crowdworking platforms. Rasch Measurement Theory analysis was employed to refine the scale and examine its psychometric properties. RESULTS: The field-test sample included 2129 participants. The 15-item scale was reduced in length to 11 items. Data from the sample fit the Rasch model (X2 [99] = 21.32, P = 0.06). All items had ordered thresholds and mapped out a targeted clinical hierarchy. The reliability statistics for the person separation index was 0.94 and for Cronbach's alpha was 0.97. In terms of validity, worse scores on the cellulite scale were associated with being more bothered by how the cellulite looked overall, having more severe cellulite on the Patient-Reported Photo-numeric Cellulite Severity Scale, and having more self-reported cellulite and more areas of the body with cellulite. CONCLUSIONS: The BODY-Q cellulite scale can be utilized to measure appearance of cellulite and provides a solid basis for future studies evaluating the impact of cellulite and its treatment.