title: Validation of a multivariate model predicting presence and size of varices.
abstract: BACKGROUND
  A model developed by our group identified low platelets and advanced Child-Pugh class (CPC) as being associated with large varices.
  
  
  OBJECTIVE
  To validate a defined cut-off of platelets < or =80,000/microL in CPC-A for large varices and platelets < or =90,000/microL in CPC-B/C for any varices.
  
  
  METHODS
  Validation cohorts consisted of patients with cirrhosis undergoing screening for varices from Oregon Health and Science University (n=152), Indiana University (n=252), and Genoa, Italy (n=101). Similar clinical and laboratory data were collected as for the original cohort. To assess the ability of these cut-offs to predict presence of large and any varices, sensitivity, specificity, positive and negative predictive values, likelihood ratios, and the c-statistic were measured.
  
  
  RESULTS
  The validation cohorts were statistically different from the original cohort with regards to CPC and prevalence of large varices. Combining the original (n=301) and validation cohorts resulted in a negative predictive value of 92.1% for platelets < or =80,000/microL in CPC-A for large varices and positive predictive value of 80.1% for platelets < or =90,000/microL in CPC-B/C for any varices. Combining the 4 cohorts yielded a c-statistic of 0.67 (95% confidence interval: 063-0.72). No other factors such as splenomegaly and Model for End-Stage Liver Disease score were identified as significant.
  
  
  CONCLUSIONS
  This study confirms the validity of a previous model identifying low platelets and advanced CPC class as predictors of large varices. Despite combining the cohorts, no other risk factors were identified.
authors.affiliation: Division of Gastroenterology and Hepatology, University of Colorado Health Sciences University, Denver, CO 80262, USA. James.Burton@UCHSC.edu
authors.forename: James R
authors.initials: JR
authors.lastname: Burton
authors.forename: Suthat
authors.initials: S
authors.lastname: Liangpunsakul
authors.forename: Jodi
authors.initials: J
authors.lastname: Lapidus
authors.forename: Edoardo
authors.initials: E
authors.lastname: Giannini
authors.forename: Naga
authors.initials: N
authors.lastname: Chalasani
authors.forename: Atif
authors.initials: A
authors.lastname: Zaman
mesh_terms: D000328:Adult; D004932:Esophageal and Gastric Varices / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D005260:Female; D005544:Forecasting; D006801:Humans; D016013:Likelihood Functions; D008103:Liver Cirrhosis / Q000150:complications; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D010976:Platelet Count; D012372:ROC Curve; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index