A photographic scale for the assessment of human facial wrinkles

Abstract

We report the utility of photographic scales to assess the degree of human facial wrinkles. A five-grade photo scale of wrinkles at eye corners was developed using photos obtained from 411 female participants aged 17 to 83 years. Based on this photo scale, scorings (five grades and nine grades) of all photos were performed by two specialists, and a standard photo for each wrinkle grade was obtained. In addition, in order to evaluate the influence of inter-observer differences in grading criteria, another scoring was performed by five general observers. The agreement between the grade standard and the score given by the general observers was evaluated by calculating the chance-corrected coefficient, i.e., the kappa value. The degree of agreement for the five-grade scale was more consistent than that for the nine-grade scale system, in which the kappa values were 0.499 and 0.396, respectively. When scoring was performed using the five-grade photo scale for the eye corners after 15 participants used a wrinkle-improving agent, a significant reduction of the wrinkle scores was confirmed. Taken together, the present findings indicate that the five-grade wrinkle photo scale is valid and useful to assess the degree of facial wrinkles.