Background: A naturally aged face is often characterized by a noticeable lack of jawline contour and decreased volume in the lower region. Several options are available to redefine the jawline. To objectively evaluate treatment-related improvements in clinical practice and research, a validated photonumeric scale is needed.
Objective: To present scale-development methods for the Merz Jawline Assessment Scale and establish its reliability.
Methods: A 5-point photonumeric scale was developed to objectively assess jawline volume loss and contour disruption using male and female subjects of various ages and skin types. Seven board-certified dermatologists and plastic surgeons evaluated 90 subjects live in 2 sessions, 3 weeks apart to establish intra- and interrater reliability.
Results: The weighted kappa for intra- and interrater agreement were ≥ 0.7 in all cases. Intrarater agreement between the 2 rating sessions was nearly perfect (median weighted kappa = 0.908). Substantial interrater agreement between each rater pair was also demonstrated for both rating sessions.
Conclusion: The Merz Jawline Assessment Scale is a validated and reliable photonumeric scale for rating loss of jawline volume and contour. The scale maintains its validity and reliability with reproducible results across a diverse group of males and females of various ages and Fitzpatrick skin types. J Drugs Dermatol. 2023;22(2):203-209. doi:10.36849/JDD.7193.