OBJECTIVES : To identify characteristics, symptoms, impacts, and satisfaction concepts associated with masseter prominence in US-based participants; and evaluate the content validity of the Lower Facial Shape Questionnaire (LFSQ) patient-reported outcome (PRO) measure originally developed for use in primarily Asian populations.

METHODS : Participants ≥18 years old with investigator-assessed masseter prominence, were recruited from 3 US sites. Hybrid concept elicitation (CE) and cognitive debriefing (CD) interviews were conducted to 1) document the relevant characteristics, symptoms, impacts, and condition-related satisfaction concepts of masseter prominence and 2) evaluate the participants’ ability to read, understand, and complete the LFSQ assessments (symptoms, impacts, and satisfaction). Important and relevant concepts were organized into a conceptual model and compared to the content of the LFSQ.

RESULTS : The study included 20 participants (mean age 41 (SD=15); 75% female; 60% Caucasian) who were mainly classified with moderate or marked masseter prominence (65%). The most commonly reported masseter prominence characteristics included shape (75%; eg, square), volume (50%; eg, full), and characterizations (55%; eg, pronounced). The most frequently reported symptoms were grinding teeth and jaw pain (45% each). The most frequently mentioned impacts were emotional (75%; eg, self-conscious) and social (40%; eg, shyness). Participants reported that successful treatment would include improved appearance (45%), facial symmetry (35%), and reduced symptoms (35%). Review of the CE in comparison to the existing concepts of LFSQ demonstrated that frequently-reported concepts were included. Cognitive debriefing demonstrated that the LFSQ was relevant to the masseter prominence experience and easy to use.

CONCLUSIONS : Results confirmed the content validity of the LFSQ regarding its use in mainly Caucasian participants with masseter prominence. The psychometric properties of the LFSQ need to be evaluated to further support validity and reliability.