Methods for the health technology assessment of complex interventions: a protocol for a scoping review

In healthcare policy and economic literature, research on the health technology assessment (HTA) of complex interventions (CIs) is becoming increasingly important. In many developed countries, HTA guides decision-making to help achieve greater value for money when funding health care. However, research has yet to identify the forms of evidence and evaluation criteria that should be used in the HTA of CIs. Previous research has established that the HTA of CIs requires multiple factors to be evaluated but there is no agreement on which factors ought always to be considered. There is equally little agreement on which forms of evidence ought to be collected or synthesised and how. We plan to perform a systematic scoping review in order to identify the range of evaluation criteria and types of evidence currently used in the HTA of CIs.

This protocol was developed to guide the methodological framework for the conduct of a scoping review on health technology assessment (HTA) of complex interventions (CIs), using the Joanna Briggs Institute guidelines and the six-stage framework proposed by Arksey and O'Malley, in addition to more recent innovations in scoping review methodology. A grey literature search will supplement the primary searches of seven electronic databases for studies available in English between January 2000 and August 2020. Two reviewers will independently screen all search results for inclusion and data will be extracted using a customised data extraction or charting form. Any dispute will be resolved by consensus or through arbitration by a third author. The mnemonic Population, Concept and Context will be adopted to establish criteria for selecting relevant literature, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses: Extension for Scoping Review will be used for reporting the results. Several explanatory-descriptive methods will be used for analysing the extracted data including frequency and trend analyses as well as reflexive thematic coding and analysis.Mapping evidence on the HTA of CIs will allow us to gain a better understanding of both established and emerging practices, including the information types, requirements, values and parameters that are incorporated in the HTA of CIs. We also expect the findings of the scoping review to help identify research gaps that will guide future studies. As healthcare becomes more complex in its delivery, it is timely to determine how these complex interventions should be assessed so that policy decisions can be made about whether implementation and public funding is warranted.

This scoping review will involve secondary analysis of already collected data, and thus, does not require ethics approval. The research findings will be submitted to peer-reviewed journals for publication and will also be disseminated at conferences and seminars.