title: A Microsoft-Excel-based tool for running and critically appraising network meta-analyses--an overview and application of NetMetaXL.
abstract: BACKGROUND
  The use of network meta-analysis has increased dramatically in recent years. WinBUGS, a freely available Bayesian software package, has been the most widely used software package to conduct network meta-analyses. However, the learning curve for WinBUGS can be daunting, especially for new users. Furthermore, critical appraisal of network meta-analyses conducted in WinBUGS can be challenging given its limited data manipulation capabilities and the fact that generation of graphical output from network meta-analyses often relies on different software packages than the analyses themselves.
  
  
  METHODS
  We developed a freely available Microsoft-Excel-based tool called NetMetaXL, programmed in Visual Basic for Applications, which provides an interface for conducting a Bayesian network meta-analysis using WinBUGS from within Microsoft Excel. . This tool allows the user to easily prepare and enter data, set model assumptions, and run the network meta-analysis, with results being automatically displayed in an Excel spreadsheet. It also contains macros that use NetMetaXL's interface to generate evidence network diagrams, forest plots, league tables of pairwise comparisons, probability plots (rankograms), and inconsistency plots within Microsoft Excel. All figures generated are publication quality, thereby increasing the efficiency of knowledge transfer and manuscript preparation.
  
  
  RESULTS
  We demonstrate the application of NetMetaXL using data from a network meta-analysis published previously which compares combined resynchronization and implantable defibrillator therapy in left ventricular dysfunction. We replicate results from the previous publication while demonstrating result summaries generated by the software.
  
  
  CONCLUSIONS
  Use of the freely available NetMetaXL successfully demonstrated its ability to make running network meta-analyses more accessible to novice WinBUGS users by allowing analyses to be conducted entirely within Microsoft Excel. NetMetaXL also allows for more efficient and transparent critical appraisal of network meta-analyses, enhanced standardization of reporting, and integration with health economic evaluations which are frequently Excel-based.
authors.forename: Stephen
authors.initials: S
authors.lastname: Brown
authors.forename: Brian
authors.initials: B
authors.lastname: Hutton
authors.forename: Tammy
authors.initials: T
authors.lastname: Clifford
authors.forename: Doug
authors.initials: D
authors.lastname: Coyle
authors.forename: Daniel
authors.initials: D
authors.lastname: Grima
authors.forename: George
authors.initials: G
authors.lastname: Wells
authors.affiliation: Ottawa Hospital Research Institute, Center for Practice Changing Research Building, Ottawa Hospital-General Campus, PO Box 201B, Ottawa, ON K1H 8L6, Canada. ccame056@uottawa.ca.
authors.forename: Chris
authors.initials: C
authors.lastname: Cameron
mesh_terms: D001499:Bayes Theorem; D003196:Computer Graphics; D003627:Data Interpretation, Statistical; D017147:Defibrillators, Implantable; D006801:Humans; D015201:Meta-Analysis as Topic; D012984:Software; D018487:Ventricular Dysfunction, Left / Q000628:therapy