Table 1.

Area under the curve (AUC) and 95% confidence interval (CI) of ROC curves when ranges of urine osmolality and urinary creatinine measured on a 24-h collection of urine are used to predict the 24 h urine volume and the 24 h intake of water. All calculations were based on 157 urine collections performed during both normal and increased water consumption

Volume (L)	Osmolality 50–400	Osmolality 50–600	Osmolality  > 800	Creatinine 2–6	Creatinine 2–9	Creatinine  > 15
PREDICTION OF URINE VOLUME—analysis of 24 h urine collection
AUC (95% CI)	0.87 (0.82–0.93)	0.87 (0.81–0.93)	0.89 (0.81–0.97)	0.86 (0.80–0.93)	0.84 (0.78–0.90)	0.92 (0.82–1.00)
Pos./neg	58 / 99	115 / 42	20 / 137	66 / 91	96 / 61	12 / 145
PREDICTION OF WATER INTAKE—analysis of 24-h urine collection
AUC (95% CI)	0.77 (0.70–0.85)	0.77 (0.69–0.85)	0.74 (0.63–0.85)	0.75 (0.67–0.83)	0.75 (0.67–0.82)	0.81 (0.71–0.90)
Pos./neg	58 / 99	115 / 42	20 / 137	66 / 91	96 / 61	12 / 145

Pos./neg. Number of positive and negative indications, AUC Area under the curve, 95% CI 95% confidence interval