title: Performance of platelet count/spleen diameter ratio for diagnosis of esophageal varices in cirrhosis: a meta-analysis.
abstract: BACKGROUND
  Platelet count/spleen diameter ratio (PSR) is a non-invasive method for the assessment of esophageal varices (EV), developed as an alternative to endoscopy.
  
  
  OBJECTIVE
  To assess the performance of PSR for diagnosis of EV using meta-analysis.
  
  
  METHODS
  PubMed, EMBASE, the Cochrane Library, ISI web of Knowledge, China National Knowledge Infrastructure, and article references were searched. We included studies using endoscopy as a reference standard, with the data necessary to calculate the true and false positive, true and false negative diagnostic results of PSR for EV. The quality of the studies was rated with the QUADAS tool. The hierarchical summary receiver operating characteristic (HSROC) was used to examine the PSR accuracy for the diagnosis of EV. Heterogeneity was explored using meta-regression. Clinical utility of PSR for EV was evaluated by a Fagan plot.
  
  
  RESULTS
  In 20 studies (n = 3,063), the HSROC of the PSR for EV was 0.95 at various thresholds. At the threshold of 909, the summary sensitivities and specificities were 0.92 (95% CI, 0.79-0.97) and 0.87 (95% CI, 0.76-0.93), respectively. The HSROC was also 0.95 at the threshold of 909. If PSR was below 909 for EV ("positive" result), the post-test probability (if pre-test probability was 50%) was 87%, while if PSR was at or over 909 ("negative" result), the post-test probability was only 9%. PSR also had a high accuracy in diagnosis of EV in patients with compensated cirrhosis.
  
  
  CONCLUSIONS
  PSR can identify EV in cirrhosis with a high accuracy. Application of this index may decrease the need for endoscopy among cirrhotic patients.
authors.affiliation: Department of Ultrasonography, The First Affiliated Hospital of Wenzhou Medical College, Wenzhou, China. ylskq@yahoo.com.cn
authors.forename: Li
authors.initials: L
authors.lastname: Ying
authors.forename: Xiao
authors.initials: X
authors.lastname: Lin
authors.forename: Zuo-Liu
authors.initials: ZL
authors.lastname: Xie
authors.forename: Yuan-Ping
authors.initials: YP
authors.lastname: Hu
authors.forename: Ke-Qing
authors.initials: KQ
authors.lastname: Shi
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D018572:Disease-Free Survival; D004932:Esophageal and Gastric Varices / Q000209:etiology / Q000401:mortality / Q000473:pathology*; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000150:complications / Q000401:mortality / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D010976:Platelet Count; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013154:Spleen / Q000473:pathology*; D016019:Survival Analysis