Which of the following is the correct Cockcroft-Gault Equation for CrCl as provided?

• A. (140 - age) x weight (Kg) x constant / serum creatinine (μmol)
• B. (140 - age) x weight (Kg) x constant / serum creatinine (μmol/L)
• C. (140 - age) x weight (Kg) x constant / serum creatinine (μmol) × 1.0
• D. (140 - age) x weight (Kg) ÷ serum creatinine (μmol) × constant

Answer: (A)

The formula tests your understanding that creatinine clearance by Cockcroft-Gault is proportional to (140 minus age) times body weight and is adjusted by a sex-specific constant, then divided by the serum creatinine concentration. When you use serum creatinine measured in μmol/L, the equation is written with a constant in the numerator to account for the unit conversion and the sex difference, giving CrCl in mL/min. So the correct form is CrCl = [(140 − age) × weight × constant] / serum creatinine (μmol). This captures both the need to adjust forBody size and for sex, and it uses the creatinine value in the denominator as the basis for the clearance estimate. The other options either omit or misplace the sex/unit adjustment (for example, using a fixed multiplier of 1.0) or present the same idea in a less conventional way, making the chosen form the clearest representation of the Cockcroft-Gault structure.