Glomerular filtration rate is a meaningful value in assessing and classifying the severity of chronic kidney disease. Normal glomerular filtration rate is estimated based on the patient's age; the older the age, the more glomerular filtration rate tends to decrease even without any damage to the kidney.

Glomerular filtration rate is the amount of blood filtered through the kidney in a given period of time. This index is valuable in assessing kidney function. When the glomerular filtration rate is low, it indicates that the kidney's blood filtering ability is reduced, found in acute and chronic kidney disease.