The study by Payne et al. investigates the relationship between serum calcium and protein concentrations in patients with abnormal protein levels. Two hundred consecutive serum specimens from patients requesting liver function tests were analyzed for calcium, total protein, and albumin. The results show a significant correlation between calcium and albumin (r=0.867) but a weaker correlation with total protein (r=0.482). A simple formula was derived to adjust calcium concentrations based on albumin levels: Adjusted calcium = calcium - albumin + 4.0. This adjustment ensures that the 95% limits of the observed calcium range align with the normal range determined in the laboratory. The study also highlights the importance of adjusting calcium measurements for albumin rather than total protein or specific gravity, especially in patients with hypergammaglobulinemia. The findings suggest that the adjustment based on albumin is more reliable and accurate for interpreting serum calcium concentrations.The study by Payne et al. investigates the relationship between serum calcium and protein concentrations in patients with abnormal protein levels. Two hundred consecutive serum specimens from patients requesting liver function tests were analyzed for calcium, total protein, and albumin. The results show a significant correlation between calcium and albumin (r=0.867) but a weaker correlation with total protein (r=0.482). A simple formula was derived to adjust calcium concentrations based on albumin levels: Adjusted calcium = calcium - albumin + 4.0. This adjustment ensures that the 95% limits of the observed calcium range align with the normal range determined in the laboratory. The study also highlights the importance of adjusting calcium measurements for albumin rather than total protein or specific gravity, especially in patients with hypergammaglobulinemia. The findings suggest that the adjustment based on albumin is more reliable and accurate for interpreting serum calcium concentrations.