bone density

yup still taking the liquid which was approved by my centre. I'm one of the odd ones who like the liquid blueberry chalk  it's my little liquid treat 3 times a day

Here is my lay understanding (I'm certainly no doctor or nurse): the baseline test establishes your current bone density. They take an x-ray of your spine, hips, knees. When you re-test after a period of time (say, 2 or 3 years), they take another picture of your spine/hips and compare the two. If your bone is less dense, it will be obvious when they compare. Some people have "bigger" (i.e. more dense) bones and some people have "smaller" bones. They can't take a test and necessarily know off the bat if you have an issue. But if they have something to compare to, and can see that your bones are less dense than they were 2 years ago, then an issue can be recognized.

The clinic did not order my test. It was in the paperwork I had to take to my GP prior to surgery. My GP arranged for the test. You need to arrange this ASAP.

and that makes complete sense!!  so I'm gonna book my appointment with my GP