Comparison of different instruments for measuring stratum corneum moisture content.

Synopsis Stratum corneum moisturization was measured by two instruments simultaneously on the same subjects at different body sites. One instrument is based on the 1 GH(z) focused mirowave dielectric measurement; the other instrument measures impedance at 16 Hz. A linear relationship r = 0.86 was observed between the measurements by the two above-mentioned instruments. The 1 GHz focused microwave measurement is more accurate in measuring water concentration in the stratum corneum, especially in the upper layers relevant to "moisturization"; it is, however, an expensive research instrument. The low frequency impedance measurement involves a much simpler, cheaper and portable instrument which can be used routinely to evaluate 'moisturization' for the purpose of skin classification under field conditions.