Proteinuria is an important indicator of kidney damage, and reducing proteinuria is a basic measure for treating kidney disease, so it is especially important for patients with chronic kidney disease to test urine protein regularly. Clinically, urine protein is mostly checked by qualitative urine protein, quantitative 24-hour urine protein, and 24-hour urine microalbumin methods. So what is the difference between them? How should we choose? 1.Qualitative urine protein test The result of qualitative urine protein test is indicated by “+”, the more “+”, the more protein loss. Advantages: It is convenient and easy to use. Disadvantages: The accuracy rate is low. This method is suitable for outpatient or large-scale population screening. 2.24-hour urine protein quantitative test 24-hour urine protein quantitative test is to collect 24 hours of urine and measure the content of all the proteins in it. Advantages: high accuracy and low error. Disadvantages: It is inconvenient and takes a long time to collect. It is currently recognized as the most accurate method to determine the protein content in urine, and is also an important basis for clinical diagnosis of kidney disease. 3, 24-hour urine microalbumin test In recent years, urine microalbumin has been highly valued, and the method of retention is the same as that of urine protein quantification. Advantages: It is highly sensitive to the determination of proteinuria, and is a golden indicator for the diagnosis of early kidney injury. Because of its small molecular weight, albumin is almost completely absorbed after filtration by the glomerulus and is generally rarely present in the urine. After the kidney is injured by external (ischemia, drugs), it will appear in the urine even in the early stage of injury, so urine microalbumin has high sensitivity. In addition, the urine microalbumin test can also be used as a reference indicator to determine whether a patient can stop taking medication when the kidney disease is in remission. Therefore, this test is now carried out in many units.