COLOR AND ITS MEASUREMENT 667 (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) Judd, D. B., A maxwell triangle yielding uniform ehromatieity scales, J. Opt. Soc. Am., 25, 24 (1935). Adams, E. Q., X-Z planes on the 1931 I.C.I. system of colorimetry, Ibid., 32,168 (1942). MacAdam, D. L., Visual sensitivities to color differences in daylight, Ibid., 32, 247 (1942). Hunter, R. S., Photoelectric color difference meter, Ibid., 48, 985 (1958). Judd, D. B., and Wyszeeki, G., Color in Business Science and Industry, 2nd Ed., John Wiley and Sons, Inc., New York, N.Y., 1963. Stanziola, R., Practical colour instrumentation for the dyer, Can. Textile J., 1-5 (Sep- tember 17, 1965). Kubdka, P., New contributions to the optics of intensely light scattering materials, J. Opt. Soc. Am., 38, 448, 1067 (1948). Hardy, A. C., Handbook of Colorimetry, The M.I.T. Press, Cambridge, Mass., 1936. Lieu, V. T., and Frodyma, M. M., Selection of the optimum concentration range for reflectance spectrophotometric analysis, Talanta, 13, 1319 (1966). Bornstein, M., Walsh, J. P. Munden, B. J. and Laeh, J. L., Diffuse reflectance studies of dye-adjuvant ehemisorption, J. Pharm. Sci., 56, 1410 (1967). Laehman, L., Kuramoto, R., and Cooper, J., A study of the interaction between qua- ternary ammonium compounds and several certified dyes, Ibid., 47, 871 (1958). Scott, M. W., Goudie, A. J., and Huetteman, A. J., Accelerated color loss of certified dyes in the presence of nonionic surfaetants, Ibid., 49, 467 (1960). Bornstein, M., and Lach, J. L., Diffuse reflectance studies of solid-solid interactions II, Ibid., 55, 1033 (1966).

J. Soc. Cosmetic Chemists, 19, 669-673 (Sept. 16, 1968) An Objective Method for Evaluation of Dandruff Scvcrity* PAUL FINKELSTEIN, Ph.D., and KARL LADEN, Ph.D. Synopsis--An objective method is described to evaluate the severity of dandruff in humans. This involves collecting scurf brushed from the scalp and estimating it gravimetrically. Pre- cautions are noted in the procedure so that reproducible data may be obtained. Each subject serves as his own control. Representative patterns of response are described. INTRODUCTION The technical literature on the causes and treatments of dandruff is extensive but as yet the etiology of this condition is not settled. One of the major reasons for this difficulty is the lack of an objective proce- dure for estimating the severity of the disease. For several years the authors have been using an evaluation pro- cedure which is objective and in which confidence has been developed, since it appears to be in accord with the clinical results reported for a variety of test materials. A number of subjective procedures have been proposed to evaluate the severity of dandruff (1-4). These depend mainly upon a trained ob- server (usually a dermatologist) who rates the severity of the condition on an arbitrary scale. Generally, such techniques have proved useful and commercial products have been introduced based on such studies. Recently, VanderWyk (5, 6) has reported on an objective method for measuring the severity of dandruff which is claimed to be accurate. The method involves the use of a small vacuum cleaner to collect dandruff scurf from the scalp. The scurf is then recovered and weighed. The * A substantial portion of the work reported was carried out in the research laboratories of The Toni Company, Chicago, Ill. t Gillette Research Institute, 1413 Research Blvd., Rockville, Md. 20850. 669