Grades of chronic kidney disease categorised by glomerular filtration rate (after a table by Rees et al48)
| Chronic kidney disease grade | Glomerular filtration rate (ml/min/1.73 m2) |
| Grade I | >90 |
| Grade II | 60–90 |
| Grade III | 30–60 |
| Grade IV | 15–30 |
| Grade V | <15 |
In general, serum biochemical anomalies may occur in grade II, symptoms appear in grade III, become increasingly severe in grade IV and renal replacement therapy is required in grade V.