Retraction Note
The authors have retracted this article, The impact of repeated vaccination on influenza vaccine effectiveness: a systematic review and meta-analysis. Upon reviewing the published work, the authors determined that there were a few erroneous inclusions and an omission of estimates which impacted the conclusion for the influenza A(H3N2) and influenza B analyses comparing vaccination in both years to the current year only. All authors agree to this retraction, and they have been given the opportunity to submit a revised version in the journal.
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