Program is based on the following:
Estimating Creatinine Clearance (ml/min)
Cockcroft and Gault equation:
       CrCl = (140 - age) x IBW / (Scr x 72)        (x 0.85 for females)

Estimate Ideal body weight in (kg)
 Males: IBW = 50 kg + 2.3 kg for each inch over 5 feet.
 Females: IBW = 45.5 kg + 2.3 kg for each inch over 5 feet.

Jelliffe RW. Creatinine clearance: Bedside estimate. Ann Inter Med. 1973; 79:604.
Male: (98 - (0.8 * (age - 20)) / (SCR in mg/dL)) x Patients BSA/1.73 M²
Female: Multiply above result by 0.9

(see the Multiple Clearance Calc)