Wow - this is an interesting thread!
I was forced to change GP recently, and one of the better things about it is that I now have access to my tests and prescriptions online. At my previous GP, I was given blood tests (full bloods and rheumatic factor, I thought) but it now appears I had kidney and liver function, bone, cholesterol etc, which was enlightening. I did not even know about the tests and was told everything was ok

apart from vit D which was 'deficient' (but turned out to be 38 so borderline, when I rang and asked for the number and shows as such online).
I had a kidney stone 10 years ago and apart from kidney function, that was it. I thought everything had gone back to normal, but it would appear normal includes CKD stage 2. (Also, CKD1,2 etc has changed to G1 G2 etc and is taken with ACR - albumin/creatine ratio). There was no further investigation as I was told they do not do this with a first kidney stone any more.
During the stone incident, my eGFR (estimated glomerular filtration rate) was 51 which was too low, so it was repeated and ok which turns out to be 79. From my googling the top is 100 and a normal kidney function would be 90 or over. They do not bother much unless it drops below 60, unless there are other problems such as proteinurea. This is a good website - there are tabs to click on near the top of the page which give more explanation.
http://www.renal.org/information-resources/the-uk-eckd-guide/about-egfr#sthash.jlpehmvf.dpbsMy latest result was 71, which I thought was a bit rubbish. I haven't had a urine test since I actually had the kidney stone in me (apart from a pre-op at hospital, which I assume they were happy with for anaesthetic purposes).
Part of my liver function test came back with raised bilirubin - outside the guidelines, but said normal. No idea what this is about

Also, my cholesterol has crept back up, borderline.