title: Covered Stents versus Uncovered Stents for Unresectable Malignant Biliary Strictures: A Meta-Analysis.
abstract: OBJECTIVE
  To summarize the covered or uncovered SEMS for treatment of unresectable malignant distal biliary obstruction, comparing the stent patency, patient survival, and incidence of adverse events between the two SEMSs.
  
  
  METHODS
  The meta-analysis search was performed independently by two of the authors, using MEDLINE, EMBASE, OVID, and Cochrane databases on all studies between 2010 and 2015. Pooled effect was calculated using either the fixed or the random effects model.
  
  
  RESULTS
  Statistics shows that there is no difference between SEMSs in the hazard ratio for patient survival (HR 1.04; 95% CI, 0.92-1.17; P = 0.55) and stent patency (HR 0.87, 95% CI: 0.58 to 1.30, P = 0.5). However, incidence of adverse events (OR: 0.74, 95% CI: 0.57 to 0.97, P = 0.03) showed significant different results in the covered SEMS, with dysfunctions events (OR: 0.75, 95% CI: 0.56 to 1.00, P = 0.05) playing a more important role than complications (OR: 0.87, 95% CI: 0.58 to 1.30, P = 0.50).
  
  
  CONCLUSIONS
  Covered SEMS group had lower incidence of adverse events. There is no significant difference in dysfunctions, but covered SEMS trends to be better, with no difference in stent patency, patient survival, and complications.
authors.affiliation: Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China; Zhejiang University, Zhejiang 310020, China.
authors.forename: Ming-Yu
authors.initials: MY
authors.lastname: Chen
authors.affiliation: Zhejiang University, Zhejiang 310020, China.
authors.forename: Jia-Wei
authors.initials: JW
authors.lastname: Lin
authors.affiliation: Zhejiang University, Zhejiang 310020, China.
authors.forename: He-Pan
authors.initials: HP
authors.lastname: Zhu
authors.affiliation: Zhejiang University, Zhejiang 310020, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Zhejiang University, Zhejiang 310020, China.
authors.forename: Guang-Yi
authors.initials: GY
authors.lastname: Jiang
authors.affiliation: Zhejiang University, Zhejiang 310020, China.
authors.forename: Pei-Jian
authors.initials: PJ
authors.lastname: Yan
authors.affiliation: Department of General Surgery, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, China; Zhejiang University, Zhejiang 310020, China.
authors.forename: Xiu-Jun
authors.initials: XJ
authors.lastname: Cai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000601:surgery*; D001662:Biliary Tract Surgical Procedures / Q000009:adverse effects / Q000295:instrumentation / Q000401:mortality / Q000706:statistics & numerical data; D002779:Cholestasis / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015607:Stents / Q000009:adverse effects / Q000706:statistics & numerical data