Which method provides a more accurate assessment of hypercalciuria: 24-hour urinary calcium excretion or the spot urine calcium-to-creatinine ratio?

24-hour urine should be more accurate. F. Singer

A spot urine for calcium measurement is markedly inferior to the 24-hour urinary collection. The circadian dynamics or urinary calcium excretion, related to food intake and minute to minute variability in calcium regulating hormones, like PTH and 1,25-dihydroxyvitamin D, make the spot urine unreliab...