The best overall index of renal function is considered to be glomerular filtration rate (GFR) and the gold standard for its assessment is renal inulin clearance (Cin) Unfortunately, Cin cannot be routinely used in daily practice due to its complexity as a test. The most often used ones are the Cockcroft-Gault (CG) formula and the recently developed Modification of Diet in Renal Disease (MDRD) prediction equation.
Calculation of MDRD (estimated GFR) according to this formula is simple but it requires a computer program. The following table is prepared for parts of the world where the computer program is not available as yet.