Impact of Various Body Weights and Serum Creatinine Concentrations on the Bias and Accuracy of the Cockcroft‐Gault Equation

Abstract

An unbiased C-G Cl(c) (r) can be calculated using actual body weight in underweight patients and ideal body weight in patients of normal weight. Using ABW(0.4) for overweight, obese, and morbidly obese patients appears to be the least biased and most accurate method for calculating their C-G Cl(c) (r) . Rounding S(c) (r) in patients with low S(c) (r) did not improve accuracy or bias of the Cl(cr) calculations.

Appropriateness of Dabigatran and Rivaroxaban Prescribing for Hospital Inpatients

“…26 In the 11 cases where the CrCl dropped to below 30 mL/min when ideal body weight was used, initiation of the anticoagulant was reclassified from potentially appropriate to inappropriate. The decrease in CrCl with a different method of calculation can be explained by the potential for actual body weight to overestimate renal function in overweight patients.…”

The performances of the Cockcroft-Gault, Modification of Diet in Renal Disease Study and Chronic Kidney Disease Epidemiology Collaboration equations in predicting gentamicin clearance

“…23 Using a 'midway' point in weight between the ideal and total body weight (TBW), in the form of the adjusted IBW (AIBW), has thus been advocated…”

“…This may be a consequence of the small number of patients (n ¼ 37) that had a low serum creatinine concentration, and the fact that the range of creatinine concentrations in this subgroup, 41-59 mmol/L, was already close to 60 mmol/ L. Another large study, which included 409 patients with serum creatinine concentrations of less than 70 mmol/L, found that this approach did not improve the performance of the Cockcroft-Gault equation for estimating creatinine clearance. 23 The data regarding the utility of setting a minimum creatinine concentration are thus conflicting.…”

Stroke Prevention in Patients With Atrial Fibrillation and Renal Dysfunction

“…The Cockcroft-Gault formula, 45 which estimates CrCl, is currently the method accepted by the US Food and Drug Administration as the basis for estimating renal function. 46 Various manipulations of body weight, such as ideal and adjusted body weight or rounding the serum creatinine value, have been suggested to improve the predictive ability of the Cockcroft-Gault formula 47,48 ; however, the National Kidney Foundation calculator uses actual body weight, which is consistent with the method used in the recent clinical trials evaluating NOACs. 46 Other methods, such as the Modification of Diet in Renal Disease and the Chronic Kidney Disease Epidemiology Collaboration, which estimate GFR, are also used.…”