Table 3.
Age-Specific and Sex-Specific Pediatric Reference Intervals for Electrolyte Levels
| Analyte | Unit | Age | Sex | No. | Lower Limit (95% Confidence Interval) | Upper Limit (95% Confidence Interval) |
|---|---|---|---|---|---|---|
| Potassium | mmol/L | 1 mo to <18 y | F + M | 6,466 | 3.76 (3.73-3.77) | 5.18 (5.16-5.19) |
| Sodium | mmol/L | 1 mo to <3 y | F + M | 875 | 131.9 (131.7-132.1) | 140.6 (140.4-141.2) |
| 3-<9 y | F + M | 2,014 | 133.3 (133.1-133.4) | 143.0 (142.8-143.1) | ||
| 9-<18 y | F + M | 3,577 | 135.2 (135.1-135.3) | 144.2 (144.1-144.3) | ||
| Chlorine | mmol/L | 1 mo to <18 y | F + M | 6,466 | 97.4 (97.3-97.5) | 105.7 (105.7-105.8) |
| Calcium | mg/dL | 1 mo to <2 y | F + M | 407 | 9.62 (9.54-9.66) | 11.38 (11.26-11.42) |
| 2-<6 y | F + M | 1,713 | 9.38 (9.34-9.42) | 11.30 (11.26-11.34) | ||
| 6-<18 y | F + M | 4,346 | 9.14 (9.10-9.18) | 10.98 (10.98-11.02) | ||
| Magnesium | mg/dL | 1 mo to <18 y | F + M | 6,466 | 1.58 (1.58-1.60) | 2.19 (2.19-2.19) |
| Phosphorus | mg/dL | 1 mo to <1 y | F + M | 144 | 5.11 (4.92-5.27) | 6.88 (6.85-6.88) |
| 1-<11 y | F + M | 3,589 | 4.52 (4.52-4.55) | 6.47 (6.44-6.50) | ||
| 11-<13 y | M | 554 | 4.52 (4.46-4.58) | 6.85 (6.81-6.88) | ||
| F | 597 | 3.90 (3.87-3.96) | 6.47 (6.38-6.50) | |||
| 13-<15 y | M | 372 | 4.03 (3.96-4.09) | 6.75 (6.69-6.85) | ||
| F | 381 | 3.75 (3.69-3.81) | 5.92 (5.82-6.13) | |||
| 15-<17 y | F + M | 577 | 3.87 (3.87-3.90) | 5.61 (5.48-5.76) | ||
| 17-<18 y | F + M | 252 | 3.56 (3.53-3.56) | 5.08 (5.02-5.11) |