OBJECTIVES:

Conceptual modelling (CM) is a key initial step in developing a mathematical model. Whilst there are established CM frameworks in other disciplines there has been little research in the field of economic evaluation, and no generic standardised frameworks exist. The objective of this research was to identify CM frameworks in non-economic evaluation fields, and to analyse these frameworks for common steps that would inform the development of a CM framework for economic evaluation.

METHODS:

After an initial scoping exercise using pearl growing techniques, a qualitative critical interpretive synthesis (CIS) approach was used to identify frameworks and synthesize results. CIS uses an iterative approach to search a range of sources, followed by an evolving selection and synthesis process to add to the research.

Web of Science was purposefully searched to identify CM frameworks, broad inclusion criteria included CM frameworks with discrete steps, references and citations were examined. Alongside this a site-ation search was carried out to identify non-academic frameworks.

An iterative data extraction process identified common steps in the frameworks, these were analysed and used to inform a framework for economic evaluation CM.

RESULTS:

Fifteen frameworks were identified from disciplines including ecology and engineering. Regardless of the discipline, similar steps were identified in each framework, ranging from two to nine steps. Using these steps, a CM framework for economic evaluation is proposed, split into three broad sections: understanding the problem (including; choose project team, objectives and outputs), model content (including; review previous conceptual models, scope and detail) and documenting the conceptual model (including review/refine, validation and assumptions/simplifications).

CONCLUSIONS:

Using steps from non-economic evaluation frameworks has informed a CM framework proposed for use in economic evaluation. The next stage in this research is to validate the framework with expert opinion and case studies.