1. CCR overestimates GFR especially in chronic renal failure. This has been attributed to tubular secretion of creatinine, to fluctuations in the daily creatinine formation and excretion, and to interference of creatinine chromogenic material with the Jaffe reaction (Lubowitz et;Kim;al; It has been known for a long time, that Cu,,. underestimates GFR and is highly dependent on dietary protein intake. On the other hand, Lubowitz,1967
2. Recently isotopic single injection clearance techniques have become increasingly popular for the estimation of true GFR because of their simplicity, accuracy, and noninvasive nature. CEDTA has been tested in large groups of children with normal or slightly impaired renal function (Vogeli;Chantler; Barratt;et al; Few data, however, have been published on the determination of GFR by CEDTA in children with advanced chronic renal failure (Vogeli,1971
3. This has the extracellular volume, present even in the absence of overt oedema
4. Clinical assessment of renal function. Pediatric Nephrology;Barratt, T.M.; Chantler, C.,1975
5. Determination of glomerular filtration rate in the newborn;Broberger, U.;Acta Paediatrica Scandinavica,1973