The challenge of assessing quality and synthesising evidence: Lessons from an overview of systematic reviews of economic evaluations of vaccination programmes




Short oral session 1: Improving conduct and reporting of evidence synthesis


Wednesday 13 September 2017 - 11:00 to 12:30


All authors in correct order:

Hadnorntun P1, Bangpan M2, Taychakhoonavudh S1, Thavorn K3, Ng SS4, Chaiyakunapruk N5
1 Chulalongkorn University, Thailand
2 University College London, UK
3 Ottawa Hospital Research Institute, The Ottawa Hospital, Ottawa, Canada
4 School of Pharmacy, Monash University, Malaysia, Selangor, Malaysia
5 School of Pharmacy, Monash University, Malaysia, Selangor, Malaysia
Presenting author and contact person

Presenting author:

Nathorn Chaiyakunapruk

Contact person:

Abstract text
Background: Although there are a large number of published systematic reviews (SRs) of economic evaluations (EEs) of vaccination programs used to support policy decision making, the overall summary of findings from these SRs lacks of consensus, and the overall quality of these SRs has not been critically appraised.
Objectives: To assess methodological quality of SRs and summarize overall findings of EEs of each vaccination.
Methods: We searched PubMed, Embase, Cochrane library, Scopus, Web of science and PsycInfo from inception to 31 May 2017. No language restriction was applied. We extracted information on general information, search strategies, inclusion criteria, data extraction, study characteristics, and overall summary of the findings of SRs. We assessed quality of SRs using ROBIS.
Results: A total of 89 SRs of EEs of vaccination programs was identified. Most studies (83%, 74/89) focused on the evaluation of single vaccine (either monovalent or combined vaccine), while 15 studies (17%) included several vaccines into their analysis. Reviews were mostly on HPV (20%, 18/89), followed by influenza (17%, 15/89), and pneumococcal vaccines (12%, 11/89). Overall findings showed that some vaccination programs (e.g. dengue, chickenpox, herpes zoster, hepatitis B) were cost-effective in general, while some (e.g. pneumococcal, rotavirus, hepatitis A) provided inconsistent conclusions, depended on vaccine prices, vaccine efficacy, duration of protection, discount rate, incidence of the disease or inclusion of herd immunity in the analysis. Half of the SRs (51%, 45/89) did not mention the quality assessment of EEs included. Among those reporting quality assessment, we found a variation of tools used.
Conclusions: Our findings suggest a wide variation of reporting methods of SRs of EEs. Standardization of these reporting methods may be needed. The overall summary of findings from SRs shows that some vaccinations are generally cost-effective, but in some vaccinations, the absolute consistent conclusions cannot be drawn.