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Surface pH of Normal Skin
Abstract:
The skin furface pH of 55 brown-skinned individuals (Indians) comprising of 30 males and 25 females in the age range 12-58 years has been measured at the forehead (FH) and the back of the wrist (BW). The mean values of skin pH at FH and BW are 5.51 + 0.32 and 5.56 + 0.40 respectively for male. The corresponding female values are 5.73 + 0.032 and 5.84 + 0.28 statistical analysis of the data shows that (i) the dependence of skin surface pH on age is not significant, (ii) the male skin is slightly, but significantly more acidic than the female one, (iii) the mean values of skin pH at forehead and at back of the wrist do not differ significantly for male ; the difference however is significant for female at 5% level, (iv) there exists a significant positive correlation ( r=0.77 for male and r + 0.71 for female) between the pH's of the forehead (x2) and the back of the wrist (z3). The regression equation of x2 on x3 are: x2= 2.13+0.61 for male and x2=1.05 + 0.80x3 for female.
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