title: Thigh length versus knee length antiembolism stockings for the prevention of deep vein thrombosis in postoperative surgical patients; a systematic review and network meta-analysis.
abstract: OBJECTIVE
  To assess the clinical effectiveness of thigh length versus knee length antiembolism stockings for the prevention of deep vein thrombosis (DVT) in surgical patients.
  
  
  METHODS
  Systematic review and meta-analysis using direct methods and network meta-analysis.
  
  
  METHODS
  Previous systematic reviews and electronic databases were searched to February 2014 for randomised controlled trials (RCTs) of thigh length or knee length antiembolism stockings in surgical patients. Study quality was assessed using the Cochrane Risk of Bias Tool. The primary outcome was incidence of DVT. Analysis of the DVT data was performed using ORs along with 95% CIs. The I(2) statistic was used to quantify statistical heterogeneity.
  
  
  RESULTS
  23 RCTs were included; there was substantial variation between the trials and many were poorly reported with an unclear risk of bias. Five RCTs directly comparing thigh length versus knee length stockings were pooled and the summary estimate of effect favouring thigh length stockings was not statistically significant (OR 1.48, 95% CI 0.80 to 2.73). 13 RCTs were included in the network meta-analysis; thigh length stockings with pharmacological prophylaxis were more effective than knee length stockings with pharmacological prophylaxis, but again results were not statistically significant (OR 1.76, 95% credible intervals 0.82 to 3.53).
  
  
  CONCLUSIONS
  Thigh length stockings may be more effective than knee length stockings, but results did not reach statistical significance and the evidence base is weak. Further research to confirm this finding is unlikely to be worthwhile. While thigh length stockings appear to have superior efficacy, practical issues such as patient acceptability may prevent their wide use in clinical practice.
  CRD42014007202.
authors.affiliation: Centre for Reviews and Dissemination, University of York, York, UK.
authors.forename: Ros
authors.initials: R
authors.lastname: Wade
authors.affiliation: Centre for Reviews and Dissemination, University of York, York, UK.
authors.forename: Fiona
authors.initials: F
authors.lastname: Paton
authors.affiliation: Centre for Reviews and Dissemination, University of York, York, UK.
authors.forename: Stephen
authors.initials: S
authors.lastname: Rice
authors.affiliation: Northern Vascular Centre, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK.
authors.forename: Gerard
authors.initials: G
authors.lastname: Stansby
authors.affiliation: Department of Spinal Surgery, Leeds Teaching Hospitals NHS Trust, Leeds, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Millner
authors.affiliation: Department of Pathology, Royal Bournemouth and Christchurch Hospitals NHS Foundation Trust, Bournemouth, UK.
authors.forename: Hayley
authors.initials: H
authors.lastname: Flavell
authors.affiliation: Centre for Reviews and Dissemination, University of York, York, UK.
authors.forename: Dave
authors.initials: D
authors.lastname: Fox
authors.affiliation: Centre for Reviews and Dissemination, University of York, York, UK.
authors.forename: Nerys
authors.initials: N
authors.lastname: Woolacott
mesh_terms: D004867:Equipment Design; D005343:Fibrinolytic Agents / Q000009:adverse effects / Q000627:therapeutic use; D006801:Humans; D007717:Knee; D011183:Postoperative Complications / Q000517:prevention & control*; D011655:Pulmonary Embolism / Q000209:etiology; D053828:Stockings, Compression / Q000009:adverse effects; D013848:Thigh; D020246:Venous Thrombosis / Q000150:complications / Q000517:prevention & control*
chemical_list: D005343:Fibrinolytic Agents
keywords: SURGERY; VASCULAR MEDICINE