Development and Validation of the Patient-Reported Submental Fat Rating Scale and the Patient-Reported Submental Fat Impact Scale

BACKGROUND No validated assessment tools are available to evaluate patient-reported outcomes specifically related to submental fat (SMF). OBJECTIVE To develop and validate scales measuring the severity (Patient-Reported SMF Rating Scale [PR-SMFRS]) and psychological impact (Patient-Reported SMF Impact Scale [PR-SMFIS]) of SMF. MATERIALS AND METHODS A literature review, content validation interviews (concept elicitation [ n = 29] and cognitive debriefing [ n = 15]) in adults with SMF, and expert interviews ( n = 3) were conducted to develop the PR-SMFRS and PR-SMFIS. Psychometric validity (acceptability, reliability, and validity) for the PR-SMFRS and PR-SMFIS was assessed using data from 1 phase 2 and 5 phase 3 ATX-101 studies in patients with excess SMF. RESULTS The PR-SMFRS was constructed as a single-item, 5-point rating of the SMF amount/size. The PR-SMFIS was constructed as a 6-item scale, with an 11-point numeric rating for each item. Both scales demonstrated acceptable psychometric properties (test–retest reliability and internal consistency). The anchor-based minimally important difference analysis suggests a 1-point improvement on the PR-SMFRS (scale of 0‒4) and a 3-point improvement on the PR-SMFIS (scale of 0‒10) represent clinically meaningful change. CONCLUSION The PR-SMFRS and PR-SMFIS are reliable, valid instruments for assessing the severity and psychosocial impact, respectively, of SMF and detecting clinically meaningful change with intervention.