Table 1.
Prediction equations used to estimate 24 h urinary creatinine excretion (PrCr).
| Equation for Estimating Predicted 24 h Creatinine Excretion | Notes | Reference |
|---|---|---|
| Pr24hCr (mg/day) = (−2.04 × age (year)) + (14.89 × weight (kg)) + (16.14 × height (cm)) − 2244.45. | Developed in 591 Japanese adults aged 20–59 year | Tanaka, T.; Okamura, T.; Miura, K.; Kadowaki, T.; Ueshima, H.; Nakagawa, H.; Hasimoto, T. A simple method to estimate populational 24-hour urinary sodium and potassium excretion using a casual urine specimen. J. Hum. Hypertens 2002, 16, 97–103. [26] |
| Pr24hCr (mg/day) for men = (12.63 × age (year)) + (15.12 × weight (kg)) + (7.39 × height (cm)) – 79.9 Pr24hCr (mg/day) for women = (−4.72 × age (year)) + (8.58 × weight (kg)) + (5.09 × height (cm)) − 74.5 |
Equation for predicted 24-h urine creatinine excretion developed in a study of 256 male and 231 female participants aged 20–79 year [30] and validated in 20 male and 27 female Japanese and foreign (including 16 American) subjects. | Kawasaki, T.; Itoh, K.; Uezono, K.; Sasaki, H. A simple method for estimation of 24 h urinary sodium and potassium excretion from second morning voiding urine specimens in adults. Clin. Exp. Pharmacol. Physiol. 1993, 20, 7–14. [27] |
| Pr24hCr (mg/day) for men = 0.00179 × (140 − age (year)) – (weight (kg)1.5 × height (cm)0.5) × (1 + 0.18 × A × (1.366–0.0159 × BMI (kg/m2)) Pr24hCr (mg/day) for women = 0.00163 × (140 − age (year)) × (weight (kg)1.5 × height (cm)0.5) × (1 + 0.18 × A × (1.429–0.0198 × BMI (kg/m2)), where A is African American or black race = 1, other race = 0. |
The Mage equation was developed to predict urine pesticide and chemical exposure with NHANES urine specimens. Equation for predicted 24-h urine creatinine excretion developed in a separate study [31] of 249 men in Canada with corrections based on the relative amounts of fat and muscle mass in women and differences in muscle mass by race and BMI. | Mage, D.T.; Allen, R.H.; Kdali, A. Creatinine corrections for estimating children’s and adult’s pesticide intake doses in equilibrium with urinary pesticide and creatinine concentrations. J. Expo. Sci. Environ. Epidemiol.
2008, 18, 360–368. [28] Huber, D.R.; Blount, B.C.; Mage, D.T.; Letkiewicz, F.J.; Kumar, A.; Allen, R.H. Estimating perchlorate exposure from food and tap water based on US biomonitoring and occurrence data. J. Expo. Sci. Environ. Epidemiol. 2011, 21, 395–407. [32] |
Table adapted from Cogswell et al. (2013) [33].