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297 J. Cosmet. Sci., 73, 297–313 (September/October 2022) Address all correspondence to Di Qu, dqu1100@comcast.net Characterizing and Modeling Complexion by Panel Perception and Objective Measurement of Skin Attributes From a Chinese Population DI QU, JIANWEI LIU, ZIQI WU, YINBEI CHEN, XIAOJUAN WANG AND SARAH WHITEHEAD Amway Innovation &Science, Ada, Michigan, USA (D.Q., Z.W., S.W.) Amway Innovation &Science – East Hub, Shanghai, China (J.L., Y.C., X.W.) Accepted for publication December 05, 2022. Synopsis Complexion is one of the top qualities of facial skin, which reflects conditions of health, beauty, and attractiveness. The objectives of this study were to characterize the many facets of complexion, leading to a better understanding and quantification of perceived beauty. This study examined the skin of 36 Chinese women by capturing their facial images, obtaining the opinions of “perceived ideal complexion” from 77 Chinese female panelists through paired comparison, analyzing multiple skin-surface parameters including color and textural properties, and constructing a mathematical model by statistical analysis. It was observed that skin tone and shine positively affected the perception of complexion, while pigmentary discoloration had a negative effect. A skin parameter, Ideal Complexion Score (ICS), was defined by a mathematical model that correlated complexion with basic skin properties. The model can be used to predict ICS scores from skin images. Applying the model to facial image analysis of 480 Chinese women, we show a normal distribution of ICSs in the population at large. The model was also applied to evaluating the treatment efficacy of a skin- lightening ingredient. A statistically significant improvement in ICS over the baseline was detected from the clinical images of study volunteers after 4 weeks’ use of the test formulation. INTRODUCTION A beautiful complexion is in the eye of the beholder. It is one of the top qualities of facial skin that reflects conditions of health, beauty, attractiveness, and even social status in some cultures (1–6). However, the concept of such a skin quality is often subjective and has not been rigorously quantified. Since complexion strongly relates to skin color, its perception is highly influenced by culture and ethnic background (7–14). While people in one part of the world enjoy sunbathing and pursue a tanned appearance, people in another part of the world would go extra miles to avoid exposure to the sun. Their perceptions toward “what ideal complexion is” are obviously different. Complexion is also easily affected by factors such as lack of sleep (15,16). Knowing the beauty industry strives to provide products to