Statistics and Computing

, Volume 22, Issue 5, pp 1099–1111 | Cite as

Algorithmic parameterization of mixed treatment comparisons

  • Gert van Valkenhoef
  • Tommi Tervonen
  • Bert de Brock
  • Hans Hillege
Open Access


Mixed Treatment Comparisons (MTCs) enable the simultaneous meta-analysis (data pooling) of networks of clinical trials comparing ≥2 alternative treatments. Inconsistency models are critical in MTC to assess the overall consistency between evidence sources. Only in the absence of considerable inconsistency can the results of an MTC (consistency) model be trusted. However, inconsistency model specification is non-trivial when multi-arm trials are present in the evidence structure. In this paper, we define the parameterization problem for inconsistency models in mathematical terms and provide an algorithm for the generation of inconsistency models. We evaluate running-time of the algorithm by generating models for 15 published evidence structures.


Mixed treatment comparison Network meta-analysis Indirect comparisons Evidence consistency Model generation Algorithm 

Supplementary material

11222_2011_9281_MOESM1_ESM.pdf (109 kb)
Evidence Structures (PDF 109 kB) (11 kb)
(ZIP 12 kB)


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Copyright information

© The Author(s) 2011

Authors and Affiliations

  • Gert van Valkenhoef
    • 1
    • 2
  • Tommi Tervonen
    • 3
  • Bert de Brock
    • 2
  • Hans Hillege
    • 1
  1. 1.Dept. of EpidemiologyUniversity Medical Center GroningenRB GroningenThe Netherlands
  2. 2.Faculty of Economics and BusinessUniversity of GroningenGroningenThe Netherlands
  3. 3.Econometric InstituteErasmus University RotterdamRotterdamThe Netherlands

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