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Published on: June 4, 2014
Development and Validation of a Photonumeric Scale for Evaluation of Lip Fullness
Background:
The shape, proportion, and fullness of one's lips are associated with overall facial beauty and attractiveness. Lip augmentation, due to personal preference or to reverse natural aging, has become a standard clinical procedure to improve lip volume or proportion. Several options are available to redefine the lips. 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 Lip Fullness Assessment Scale (MLFAS) and establish its reliability.
Methods:
A 5-point photonumeric scale was developed to objectively assess loss of lip volume using male and female subjects of various ages and skin types. To establish intra- and interrater reliability, 8 board-certified dermatologists and plastic surgeons evaluated 64 subjects live in 2 sessions, 2 weeks apart.
Results:
The weighted kappa for intra- and interrater agreement were ≥ 0.6 in all cases. Intrarater agreement between the 2 rating sessions was nearly perfect (median weighted kappa = 0.911 and 0.930 for the upper lip and lower lip, respectively). Substantial interrater agreement between each rater pair was also demonstrated for both rating sessions, and ratings of upper and lower lip fullness showed comparable reliability.
Conclusion:
The MLFAS is a validated and reliable photonumeric scale for rating loss in lip volume. The scale maintains its reliability with reproducible results across a diverse group of males and females of various ages and Fitzpatrick skin types. J Drugs Dermatol. 2023;22(3): doi:10.36849/JDD.7309.

