Reference interval for albumin-adjusted calcium based on a large UK population.

We have established an upper limit of the reference range for older women that would identify all high outliers (2.60 mmol/L and above). The upper limit for young women and for men is lower, at 2.57 and 2.55 mmol/L respectively. The current reference interval in use has to be updated and improved based on these findings. These upper limits may prove helpful for identifying hypercalcaemic disorders like primary hyperparathyroidism in clinical practice.