j. Soc. Cosmet. Chem., 42, 385-391 (November/December 1991) Comparative studies of skin roughness measurements by image analysis and several in vivo skin testing methods KARLHEINZ SCHRADER and STEPHAN BIELFELDT, Creachem GmbH, Research Institute for the Cosmetics Industry, Max-Planck-Stra?e 6, D-3450 Holzminden, Germany. Received October 24, 1989. Synopsis Measurement of skin roughness on the volar forearm in humans using image analysis correlates significantly with skin moisture assessment by measuring the dielectric constant of skin (r = 0.57), skin roughness measurement by methylene blue adsorption (r = 0.48), and roughness measurement using a stylus instrument (0.32). This study supports the conclusion that the described image analysis method is useful in the evaluation of skin roughness. INTRODUCTION Skin roughness is a very important parameter in the characterization of cosmetic skin properties. Smooth, supple skin is a perceptible effect that can be achieved by means of cosmetic skin care. In the past twenty years many procedures have been developed to obtain direct or indirect information about skin roughness. Some methods, such as measurement of the skin's moisture content, are frequently used because a close correlation with skin rough- ness exists. In this study, an image analysis method of evaluating skin profile impressions was correlated with three other recognized procedures: moisture content by dielectric con- stant measurement, skin roughness measurement by methylene blue adsorption, and roughness measurement by profilometry. MATERIALS AND METHODS MEASURING SKIN ROUGHNESS WITH AN IMAGE ANALYSIS SYSTEM Evaluation of skin impressions by image analysis has been described principally by 385