A wide selection of data of 45 males versus those of 94 females were compared and correlated with 11 variables selected from the available variables. The estimation of creatinine clearance by the Cockroft formula was studied in depth, and both its significant correlation with measured clearances and its overestimation were noted. Scores were attributed to the p values of performed correlations to mathematically compare the correlations. The magnitude of the dispersion of the scores was evaluated by the ratio mean of the scores/standard deviation, which is the width of the range of the significance of the correlations, thus providing the relevance of the correlations for each basal variable. Lean Body Mass (LBM) was calculated, using the Boer formula as well as the serum creatinine, and it was shown that LBM was strongly related to the body structure represented by BMI. The study ofnbspnbspnbsp total body water (TBW) showed its significantly greater size in males, but it has a significantly greater size in females as a percentage of body weight . This results in a greater dry mass in males and greater body water with respect to weight in females. No differences between males and females resulted from age, the relationship of weight/height in terms of BMI, or the efficacy of treatment. It was concluded that 1) age is relevant in estimating the size of creatinine clearance, as shown by the creatinine clearance via Cockroft, but it overestimated the creatinine clearance 2) Lean Body Mass is proportional to BMI 3) the variability of statistical significance in a correlation is well defined by the scores values and 4) dry mass is significantly greater in males, while body water is greater in females in terms of percentage of weight.