EEMCO guidance for the assessment of stratum corneum hydration: electrical methods

BACKGROUND/AIMS: The improvement of stratum corneum hydration is one of the most important claims in the cosmetic industry. METHODS: Objective assessment of moisturization can be done with devices based on electrical methods provided these instruments are used in an appropriate manner. RESULTS: This paper deals with the biophysical basis behind these techniques and describes the most important variables, pitfalls and drawbacks related to measurements and current instrumentation. Individual-related and environment-related variables are also analyzed as well as study designs for predictive or use tests. CONCLUSIONS: Practical suggestions for standardization of measurements are given.