title: Evaluation of glomerular filtration rate estimation by Cockcroft-Gault, Jelliffe, Wright and Modification of Diet in Renal Disease (MDRD) formulae in oncology patients.
abstract: BACKGROUND
  The aim was to evaluate the accuracy of Cockcroft-Gault, Jelliffe, Wright and Modification of Diet in Renal Disease (MDRD) formulae as a substitute for the gold standard measure of glomerular filtration rate (GFR) using chromium 51 EDTA.
  
  
  METHODS
  Retrospective analysis of GFR measurements in oncology patients from a University Teaching Hospital over 3 years was carried out. Bias and precision of estimates of GFR were compared with measured GFR.
  
  
  RESULTS
  Six hundred and sixty patients with measured GFR (median 90 ml/min, range 23-179 ml/min) were identified. Cockcroft-Gault produced the smallest bias (median percentage error -1.4%) and highest precision (median absolute percentage error 14.0%) and was the most accurate for carboplatin dosing. For patients>30% over their ideal body weight (IBW), using IBW+30% in the Cockcroft-Gault formula was more precise than using actual body weight or IBW. The Wright formula was most accurate for patients aged 70+years and patients with a body mass index (BMI)≥30 but overestimated GFR when GFR<50 ml/min.
  
  
  CONCLUSIONS
  When measured GFR is unavailable, we advise estimating GFR using the Cockcroft-Gault formula and using IBW+30% for patients weighing>30% over their IBW. If the GFR is ≥50 ml/min and the patient is >70 years and/or BMI≥30, the Wright formula gives the best estimate of GFR.
authors: Oncology Centre, Addenbrooke's Hospital, and Department of Oncology, University of Cambridge, Cambridge, UK. nicola.ainsworth@cancer.org.uk
authors: N L
authors: NL
authors: Ainsworth
authors: A
authors: A
authors: Marshall
authors: H
authors: H
authors: Hatcher
authors: L
authors: L
authors: Whitehead
authors: G A
authors: GA
authors: Whitfield
authors: H M
authors: HM
authors: Earl
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D019540:Area Under Curve; D015992:Body Mass Index; D016190:Carboplatin / Q000494:pharmacology / Q000627:therapeutic use; D054796:Drug Dosage Calculations; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy / Q000503:physiopathology; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D016190:Carboplatin