Can anyone tell me what the normal range for estimated GFR (glomerular filtration rate) is in the UK, and at what point they start saying that kidney function is deteriorating? My test results have been given in the units mL/min/1.7, and I have had results of 62.4, then several months later 55.8. When I have tried to look at reference ranges for this test using these measuring units, what I have found is that above 90 is normal, 60-90 is mild deterioration, 30-60 is moderate kidney damage. However on other sites (where the measuring units weren't specified) I have seen that 60 plus or minus 10 (i.e a range of 50-70) was normal for women. It does seem that there are several different systems of measuring units, so I really just want to know where my results fit into the pattern - are they normal, or are they showing the beginnings of kidney damage that I should be having monitored a bit more often. At the moment its useless asking my GP anything as his response is "I don't know, you will have to wait until you have seen the specialist"