Roughness analysis of the skin as a secondary evaluation criterion in addition to visual scoring is sufficient to evaluate ethnic differences in wrinkles

Visual scoring has been used to evaluate ethnic differences in skin wrinkling, but it is not sufficient to fully evaluate those differences in wrinkles. We examined whether both the roughness analysis of the skin and visual scoring are sufficient to characterize ethnic differences in wrinkles in Japanese, Chinese and German women. One hundred and five Japanese, 96 Chinese and 90 German age-matched women participated in this study. The severity of their wrinkles in the skin at two sites at the periphery of the eye was evaluated by visual scoring using a photoscale and by roughness values obtained from three-dimensional analysis of skin replicas. Slight but significant differences were scarcely observed between Japanese and Chinese women as well as between Japanese and German women at the same age group using the visual scoring method. However, significant and clearer differences among those ethnic groups were observed using the roughness analysis of skin replicas. Below the eye, significant differences among those ethnic groups were observed using both visual wrinkle scoring and roughness analysis. However, the extent of increased roughness values with age was relatively small compared with the increased wrinkle scores. These results show that roughness analysis is more sensitive than the visual scoring method when comparing ethnic differences in wrinkles. We conclude that roughness analysis of the skin is an important secondary evaluation criterion to visual scoring necessary to evaluate ethnic differences of wrinkles.