Internal and Emergency Medicine

, Volume 12, Issue 1, pp 103–111 | Cite as

Network meta-analysis: an introduction for clinicians

  • Benjamin Rouse
  • Anna Chaimani
  • Tianjing LiEmail author


Network meta-analysis is a technique for comparing multiple treatments simultaneously in a single analysis by combining direct and indirect evidence within a network of randomized controlled trials. Network meta-analysis may assist assessing the comparative effectiveness of different treatments regularly used in clinical practice and, therefore, has become attractive among clinicians. However, if proper caution is not taken in conducting and interpreting network meta-analysis, inferences might be biased. The aim of this paper is to illustrate the process of network meta-analysis with the aid of a working example on first-line medical treatment for primary open-angle glaucoma. We discuss the key assumption of network meta-analysis, as well as the unique considerations for developing appropriate research questions, conducting the literature search, abstracting data, performing qualitative and quantitative synthesis, presenting results, drawing conclusions, and reporting the findings in a network meta-analysis.


Network meta-analysis Multiple treatment meta-analysis Comparative effectiveness Transitivity 


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Statement of human and animal rights

The present work did not involve human participants and/or animals.

Informed consent



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Copyright information

© SIMI 2016

Authors and Affiliations

  1. 1.Center for Clinical Trials and Evidence Synthesis, Department of EpidemiologyJohns Hopkins Bloomberg School of Public HealthBaltimoreUSA
  2. 2.Department of Hygiene and EpidemiologyUniversity of Ioannina School of MedicineIoanninaGreece

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