Original Schwartz Equation
(for use with routine creatinine methods that have not been recalibrated to be traceable to IDMS)
Caution: Read here to make sure you are using the correct calculator.
GFR (mL/min/1.73 m2) = k (Height) / Serum creatinine
- k = Constant
- k = 0.33 in preemie infants
- k = 0.45 in term infants to 1 year of age
- k = 0.55 in children to 13 years of age
- k = 0.70 in adolescent males (not females because of the presumed increase in male muscle mass, the constant remains .55 for females)
- Height in cm
- Serum creatinine in mg/dL
Schwartz GJ, et al. A simple estimate of glomerular filtration rate in children derived from body length and plasma creatinine. Pediatrics. 1976 Aug;58(2):259-63.