The creatinine clearance is a measure of the glomerular filtration rate (GFR), which is, the volume of filtrate made by the kidneys per minute. The creatinine clearance is calculated after measuring the volume of urine passed in 24 hours and the urine and serum creatinine levels. A correction factor is used for body size.
The results of these tests are important in assessing the excretory function of the kidneys. For example, grading of chronic renal insufficiency and dosage of drugs that are excreted primarily via urine are based on GFR (or creatinine clearance).
