Development and Validation of a Photonumeric Scale for Evaluation of Infraorbital Hollows

BACKGROUND A validated scale is needed for objective and reproducible comparisons of infraorbital hollows (i.e., tear troughs) before and after treatment in practice and clinical studies. OBJECTIVE To describe the development and validation of the 5-point photonumeric Allergan Infraorbital Hollows Scale. METHODS The scale was developed to include an assessment guide, verbal descriptors, morphed images, and real subject images for each grade. The clinical significance of a 1-point score difference was evaluated in a review of image pairs representing varying differences in severity. Interrater and intrarater reliability was evaluated in a live-subject validation study ( N = 297) completed during 2 sessions occurring 3 weeks apart. RESULTS A score difference of ≥1 point was shown to reflect a clinically significant difference (mean [95% confidence interval] absolute score difference, 0.90 [0.79–1.02] for clinically different image pairs and 0.33 [0.19–0.46] for not clinically different pairs). Intrarater agreement between the 2 validation sessions was substantial (mean weighted kappa = 0.79). Interrater agreement was substantial during the second rating session (0.70, primary end point). CONCLUSION The Allergan Infraorbital Hollows Scale is a validated and reliable scale for physician rating severity of hollowing in the infraorbital area.