Systematic reviews (SRs) are the foundation of evidence-based medicine, but there is no gold standard for judging their methodological excellence. Although the AMSTAR tool is widely used to assess the quality of SRs, the ROBIS instrument was created relatively recently. The potential of both tools to capture the quality of SRs of interventions for increasing vaccination coverage was evaluated in this study. Two reviewers separately screened the search results, assessed research eligibility, and collected data from eligible SRs, with discrepancies resolved by consensus. Researchers used Stata 14 to perform Principal Component Analysis (PCA) to assess the similarities and differences between AMSTAR and ROBIS. The search yielded 2322 items, and 75 full-text articles were evaluated for eligibility, with 57 meeting inclusion requirements. Using AMSTAR, it was discovered that 32%, 60%, and 9% of SRs had good, moderate, and low quality, respectively. Using ROBIS, they determined that 74 percent, 14 percent, and 12 percent of SRs had a low, uncertain, or high risk of bias. PCA revealed that SRs with a low risk of bias in ROBIS grouped with good-quality SRs in AMSTAR, whereas SRs with a high risk of bias in ROBIS clustered with low-quality SRs in AMSTAR.
Findings indicate a link between methodological quality and bias risk in SRs of interventions aimed at increasing vaccination coverage. As a result, either the AMSTAR or ROBIS checklists may be used to assess the methodological quality of SRs in vaccination.