Model Structuring for Economic Evaluations of New Health Technologies


In countries such as Australia, the UK and Canada, decisions on whether to fund new health technologies are commonly informed by decision analytic models. While the impact of making inappropriate structural choices/assumptions on model predictions is well noted, there is a lack of clarity about the definition of key structural aspects, the process of developing model structure (including the development of conceptual models) and uncertainty associated with the structuring process (structural uncertainty) in guidelines developed by national funding bodies. This forms the focus of this article. Building on the reports of good modelling practice, and recognising the fundamental role of model structuring within the model development process, we specified key structural choices and provided ideas about model structuring for the future direction. This will help to further standardise guidelines developed by national funding bodies, with potential impact on transparency, comprehensiveness and consistency of model structuring. We argue that the process of model structuring and structural sensitivity analysis should be documented in a more systematic and transparent way in submissions to national funding bodies. Within the decision-making process, the development of conceptual models and presentation of all key structural choices would mean that national funding bodies could be more confident of maximising value for money when making public funding decisions.

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Correspondence to Hossein Haji Ali Afzali.

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Author Contributions

HHAA conceptualised and drafted the manuscript, and all co-authors reviewed and suggested changes. All authors reviewed and approved the final draft.


The Alan Williams Fellowship Award (Centre for Health Economics, the University of York) received by Hossein Haji Ali Afzali contributed to the conceptualisation of this article. This study was also supported by the National Health and Medical Research Council (NHMRC) of Australia via funding provided for the Centre of Research Excellence in Frailty and Healthy Ageing.

Conflict of Interest

Hossein Haji Ali Afzali is a member of the Evaluation Sub-Committee of the Medical Services Advisory Committee and Jonathan Karnon is a member of the Economic Sub-Committee of the Pharmaceutical Benefits Advisory Committee. Laura Bojke has no conflicts of interest to declare.

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Haji Ali Afzali, H., Bojke, L. & Karnon, J. Model Structuring for Economic Evaluations of New Health Technologies. PharmacoEconomics 36, 1309–1319 (2018).

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