Characteristics and methodological standards across systematic reviews with Meta-analysis of efficacy and/or effectiveness of influenza vaccines: an overview of reviews

Ref ID 897
First Author G.N. Okoli
Journal INFECTIOUS DISEASES
Year Of Publishing 2022
URL https://www.tandfonline.com/doi/full/10.1080/23744235.2022.2114537
Keywords • Vaccination
• Low methodological quality
• Low reporting quality
• Pharmacological
• Protocols
• Disclosure
• Expertise
Problem(s) • Financial conflicts of interest of review authors
• Meta-analyses and forest plots presented without considering risk of bias / quality
• Literature searches not validated by information specialist
• Reasons for excluding potentially eligible studies not provided
• Conflicts of interest or funding of included studies not assessed
• Low reporting (PRISMA) quality
• Low methodological (AMSTAR) quality
• No registered or published protocol
Article Type Empirical
Article Subtype Cross-sectional survey/Methodological systematic review
First Author Country Canada
Checklists • AMSTAR 2
Aim To systematically identify, critically appraise, and summarise the characteristics and adherence to methodological standards in Systematic Reviews with meta-analysis of efficacy/effectiveness of influenza vaccines. Only 45% percent reported protocol registration, 6% reported collaboration with a knowledge synthesis librarian/information specialist, and 60% utilised a reporting checklist (e.g. PRISMA). Of the included reviews 72% did not provide a list of excluded studies, and over half (56%) did not report the sources of funding of included studies. Thirty six reviews (75%) did not assess the risk of bias when performing a meta-analysis.
Level of Investigation Descriptive
Summary of Findings From 48 included systematic reviews of influenza vaccines indexed across MEDLINE, Embase, Scopus, CINAHL, Global Health, and CDSR up to July 11 2022. Seventy-five percent of the included reviews were of a critically methodological low quality (AMSTAR 2) and 19% were of a low quality. Excluded studies were listed and justified in only 11 reviews (23%); characteristics of studies provided in detail in just seven reviews (15%); sources of funding of included studies were not reported in over half of the reviews (56%); risk of bias was not accounted for in meta-analysis in 36 reviews (75%). 13% of the reviews were industry-funded. About 13% of the reviews were co-authored by industry employee(s). 4% of the reviews were commissioned by an organisation/authority. 45% of the reviews reported protocol registration. 6% of the reviews reported collaborating with a knowledge synthesis librarian/information specialist to prepare the search strategy. 60% of the reviews reported using the PRISMA (or similar) checklist.
Number of systematic reviews included 48
Number of eligible systematic reviews assessed 5009
Treatment impacted No
Treatment impacted description
Interpretation impacted Not Applicable
Interpretation impacted description