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Network meta-analysis of drugs

The literature shows that the use of network meta-analysis is increasing. Unlike ordinary meta-analysis, network meta-analysis enables more than two drugs with the same indication to be compared, even if these drugs have never been directly compared. In addition, network analysis can rank drugs in order of efficacy. However, performing a network meta-analysis requires specific methodological knowledge, and evaluating the results is often more difficult than with meta-analyses. Sometimes it is even impossible to estimate their value because the statistical tests to check the quality are too limited or because the researchers provide insufficient information about the precise way they implemented the network meta-analysis and the exact way they checked the results.

  • One advantage of network meta-analysis is the opportunity it provides to compare more than two drugs, even if these drugs have not been directly compared.
  • The second advantage is the opportunity to rank drugs in order of efficacy. 
  • Performing a network meta-analysis is labour-intensive and requires specific methodological expertise. 
  • The results of network meta-analyses need to be interpreted with caution. For readers it can be complicated or even impossible to determine the quality of the usually lengthy papers.
  • Network meta-analyses have to offer sufficient information about the implementation and statistical checks, such as checks on consistency, on factors that can influence the outcome (effect modifiers) and on bias in the enclosed studies. 

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  • Leo M.L. Stolk, dr