Estimation of creatinine clearance in children: comparison of six methods.

An evaluation and comparison of the accuracy of six published methods for estimating creatinine clearance from serum creatinine concentration in children are presented. The medical records of 59 patients were reviewed. The patients ranged from 1 to 18 years in age and had one or more 24-hour urine creatinine determinations completed. A total of 142 creatinine-clearance determinations were compared with the estimated creatinine clearances using each of six methods. All methods correlated well with calculated creatinine clearance. The average absolute and standard errors were greatest with the modified method of Counahan et al. and least with the method of Traub and Johnson. The error made by the method of Traub and Johnson was significantly smaller (p less than 0.05) than the error made by the methods of Schwartz et al., Counahan et al., and the modified method of Counahan et al. The method of Traub and Johnson also showed an equal tendency to overestimate and underestimate creatinine clearance. This method performed well regardless of the patients' weight, sex, or age; the method was not as accurate in children less than 107 cm in height. It is concluded that the method of Traub and Johnson for estimating creatinine clearance from serum creatinine concentration is the most accurate and nonbiased of the evaluation methods.