FEMALE/MALE ANTIPERSPIRANT EFFICACY 3 STATISTICAL ANALYSIS The source data were the milligrams of sweat output from the treated and placebo axillae at baseline and post-treatment. For the analysis comparing the effi cacy, percent reduc- tions were calculated for each test subject. The adjusted treated-to-control ratios for this analysis were calculated as follows (3,4): Percent reduction = 100 × {1 − (PC × T) / (PT × C)} where PC is the pretreatment measure of moisture for the control axilla (placebo), PT is the pretreatment measure for the test axilla, T is the treated measure for the test axilla, and C is the corresponding quantity for the control axilla (placebo). For the analysis com- paring the sweat output, the baseline average of the B and C collection milligram data across the right and left axillae were used. The study results were analyzed using Student’s t-test for independent data. The hypoth- eses for this test are shown below. Ho: The means (output/percent reductions) of the males and females were identical. Ha: The means differed. Hypothesis testing was conducted at the 0.05 level of signifi cance and no adjustments were made for the number of tests performed. RESULTS Table I indicates the number of subjects that participated in each study as well as the basic study design. The results of the statistical analyses indicate: O There was no statistically signifi cant difference between the mean percent reductions of the male and female test subjects in twelve of the fourteen time points analyzed from the eight studies. In the study where a statistically signifi cant difference was indicated (p 0.5), females had higher effi cacy, and in the one study where a directional differ- ence was seen (p 0.10), males had higher effi cacy. See Table I and Figure 1. Table I Percent Reductions for Females and Males Study Post-treatment sweat collection time point Mean percent reduction: females Mean percent reduction: males t-test p-value 1 1 Hr after application 2 27% 23% 0.5000 2 1 Hr after application 2 33% 43% 0.2924 3 1 Hr after application 4 40% 29% 0.0451* 3 24 Hr after application 4 36% 37% 0.5000 4 1 Hr after application 4 42% 40% 0.5000 4 24 Hr after application 4 35% 28% 0.2799 5 1 Hr after application 4 35% 40% 0.0844** 5 24 Hr after application 4 27% 28% 0.5000 6 1 Hr after application 4 34% 38% 0.5000 6 24 Hr after application 4 29% 30% 0.5000 7 1 Hr after application 4 23% 28% 0.4150 7 24 Hr after application 4 20% 20% 0.5000 8 1 Hr after application 4 43% 31% 0.2385 8 24 Hr after application 4 42% 32% 0.1064 *Signifi cant difference (females higher). **Directional difference (males higher).

JOURNAL OF COSMETIC SCIENCE 4 O The overall mean sweat output from the males was signifi cantly higher than that for females (p = 0.0001). This result was also seen individually in fi ve of the eight studies reviewed for sweat output (p 0.05). See Table II and Figure 2. DISCUSSION The FDA has mandated that when testing antiperspirant products that will be marketed to males, manufacturers should test the product utilizing male panels, and that when testing products marketed to females, manufacturers should use female panels (5). The data available in the literature does not indicate a physiological difference between male and female axillae. Our data indicate that in some female/male panels the male test sub- jects sweat more than the females however, we have shown that effi cacy is not related to sweat output (6). Historically, in the testing industry, female test panels have been easier to recruit and maintain than male test panels. Our results, while not conclusive, do not indicate a difference between the effi cacy achieved from male and female test subjects. We Table II Baseline Sweat Output for Females and Males. Females Males Study n Mean baseline sweat output n Mean baseline sweat output t-test p-value 1 32 405 11 657 0.0035* 2 24 476 18 478 0.5000 3 20 384 20 453 0.1864 4 21 451 20 605 0.0957 5 30 388 30 633 0.0006* 6 20 393 19 539 0.0411* 7 23 431 27 522 0.0442* 8 22 421 20 585 0.0217* Overall 192 407 165 559 0.0001* *Signifi cant difference (males higher in sweat output). Figure 1. Percent reduction (females–males).