24 hours Urine creatinine clearance
A 24 hours creatinine clearance test compares the amount of creatinine in your blood to the amount in your urine over a 24-hour period. This shows how fast your kidneys clear creatinine from your body. You must start your urine collection period with an empty bladder, then write down the time and date. This is the start time of your urine collection period and It will end 24 hours later.