title: Relative performances of FibroTest, Fibroscan, and biopsy for the assessment of the stage of liver fibrosis in patients with chronic hepatitis C: a step toward the truth in the absence of a gold standard.
abstract: OBJECTIVE
  Liver fibrosis stage is traditionally assessed with biopsy, an imperfect gold standard. Two widely used techniques, FibroTest®, and liver stiffness measurement (LSM) using Fibroscan® have been validated using biopsy, and therefore the true performances of these estimates are still unknown in the absence of a perfect reference. The aim was to assess the relative accuracy of FibroTest, LSM, and biopsy using methods without gold standard in patients with chronic hepatitis C (CHC) and controls.
  
  
  METHODS
  A total of 1289 patients with CHC and 604 healthy volunteers, with assessment of fibrosis stage by the three techniques, and alanine aminotransferase (ALT) taken as a control test, were analyzed by latent class method with random effects. In the volunteers, the false positive risk of biopsy was obtained from a large surgical sample of four normal livers.
  
  
  RESULTS
  The latent class model with random effects permitted to conciliate the observed data and estimates of test performances. For advanced fibrosis, the specificity/sensitivity was for FibroTest 0.93/0.70, LSM 0.96/0.45, ALT 0.79/0.78 and biopsy 0.67/0.63, and for cirrhosis FibroTest 0.87/0.41, LSM 0.93/0.39, ALT 0.78/0.08 and biopsy 0.95/0.51. The analysis of the discordances between pairs suggested that the variability of the model was mainly related to the discordances between biopsy and LSM (residuals>10; p<0.0001).
  
  
  CONCLUSIONS
  A method without the use of a gold standard confirmed the accuracy of FibroTest and Fibroscan for the diagnosis of advanced fibrosis and cirrhosis in patients with chronic hepatitis C. The variability of the model was mostly due to the discordances between Fibroscan and biopsy.
authors: APHP UPMC Liver Center, France. tpoynard@teaser.fr
authors: Thierry
authors: T
authors: Poynard
authors: Victor
authors: V
authors: de Ledinghen
authors: Jean Pierre
authors: JP
authors: Zarski
authors: Carol
authors: C
authors: Stanciu
authors: Mona
authors: M
authors: Munteanu
authors: Julien
authors: J
authors: Vergniol
authors: Julie
authors: J
authors: France
authors: Anca
authors: A
authors: Trifan
authors: Gilles
authors: G
authors: Le Naour
authors: Jean Christophe
authors: JC
authors: Vaillant
authors: Vlad
authors: V
authors: Ratziu
authors: Frederic
authors: F
authors: Charlotte
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D001706:Biopsy / Q000379:methods / Q000592:standards*; D016208:Databases, Factual / Q000706:statistics & numerical data; D054459:Elasticity Imaging Techniques / Q000295:instrumentation / Q000379:methods / Q000592:standards*; D005260:Female; D019698:Hepatitis C, Chronic / Q000473:pathology*; D006801:Humans; D008099:Liver / Q000473:pathology*; D008103:Liver Cirrhosis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012015:Reference Standards; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D000410:Alanine Transaminase