title: Estimation of glomerular filtration rate by a radial basis function neural network in patients with type-2 diabetes mellitus.
abstract: BACKGROUND
  Accurate and precise estimates of glomerular filtration rate (GFR) are essential for clinical assessments, and many methods of estimation are available. We developed a radial basis function (RBF) network and assessed the performance of this method in the estimation of the GFRs of 207 patients with type-2 diabetes and CKD.
  
  
  METHODS
  Standard GFR (sGFR) was determined by (99m)Tc-DTPA renal dynamic imaging and GFR was also estimated by the 6-variable MDRD equation and the 4-variable MDRD equation.
  
  
  RESULTS
  Bland-Altman analysis indicated that estimates from the RBF network were more precise than those from the other two methods for some groups of patients. However, the median difference of RBF network estimates from sGFR was greater than those from the other two estimates, indicating greater bias. For patients with stage I/II CKD, the median absolute difference of the RBF network estimate from sGFR was significantly lower, and the P50 of the RBF network estimate (n = 56, 87.5%) was significantly higher than that of the MDRD-4 estimate (n = 49, 76.6%) (p < 0.0167), indicating that the RBF network estimate provided greater accuracy for these patients.
  
  
  CONCLUSIONS
  In patients with type-2 diabetes mellitus, estimation of GFR by our RBF network provided better precision and accuracy for some groups of patients than the estimation by the traditional MDRD equations. However, the RBF network estimates of GFR tended to have greater bias and higher than those indicated by sGFR determined by (99m)Tc-DTPA renal dynamic imaging.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China. bmxmwus@scut.edu.cn.
authors.forename: Xun
authors.initials: X
authors.lastname: Liu
authors.forename: Yan-Ru
authors.initials: YR
authors.lastname: Chen
authors.forename: Ning-shan
authors.initials: NS
authors.lastname: Li
authors.forename: Cheng
authors.initials: C
authors.lastname: Wang
authors.forename: Lin-Sheng
authors.initials: LS
authors.lastname: Lv
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Wu
authors.forename: Tan-Qi
authors.initials: TQ
authors.lastname: Lou
mesh_terms: D000465:Algorithms; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology*; D003929:Diabetic Neuropathies / Q000175:diagnosis* / Q000209:etiology; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D016571:Neural Networks, Computer; D010363:Pattern Recognition, Automated / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity