Patient: Can you interpret my serum Collagen 1 C telopep CTx result? The report states the’reference range’ for a 45 yr old women is 40-465 pg ml. My score was 438. I am not on any bisphonates. I do have osteopenia according to a recent bone density dexa test. Since the ref range is so wide and Im in the high end of it, does this mean my bone resorption is too high? Ive had a litany of other lab tests and nothing else points to why I have low bone mass.