ArticleVaccine: X2019
Vaccination history as a confounder of studies of influenza vaccine effectiveness.
Article in Vaccine: X, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
18 citing papers in PubMed.
- Validity of influenza vaccine effectiveness calculations using a test-negative design in Thailand.American journal of epidemiology · 2026Article
- Influenza vaccine effectiveness against outpatient acute respiratory illness with laboratory-confirmed influenza, United States, 2024-25 season.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2026Article
- Influenza vaccine effectiveness against outpatient acute respiratory illness with laboratory-confirmed influenza, United States, 2024-25 season.medRxiv : the preprint server for health sciences · 2026Article
- Effectiveness and Impact of Autumn 2023 COVID-19 Vaccination in Preventing Hospitalizations in Navarre, Spain, October 2023 to September 2024.Influenza and other respiratory viruses · 2025Article
- Improved Methods for Vaccine Effectiveness Studies.The Journal of infectious diseases · 2025Article
- Effectiveness of influenza vaccination in preventing confirmed influenza cases and hospitalizations in Northern Spain, 2023/24 season: A population-based test-negative case-control study.International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases · 2025Article
- Seasonal Influenza Vaccine Effectiveness in Persons Aged 15-64 Years: A Systematic Review and Meta-Analysis.Vaccines · 2023Review
- Article
- Protecting pregnant people & infants against influenza: A landscape review of influenza vaccine hesitancy during pregnancy and strategies for vaccine promotion.Human vaccines & immunotherapeutics · 2022Review
- Influence of Prior Influenza Vaccination on Current Influenza Vaccine Effectiveness in Children Aged 1 to 5 Years.Vaccines · 2021Article
- Influenza Vaccine Effectiveness for Prevention of Severe Influenza-Associated Illness Among Adults in the United States, 2019-2020: A Test-Negative Study.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2021Article
- Spotlight influenza: Estimation of influenza vaccine effectiveness in elderly people with assessment of residual confounding by negative control outcomes, Finland, 2012/13 to 2019/20.Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2021Article
- Effects of Prior Season Vaccination on Current Season Vaccine Effectiveness in the United States Flu Vaccine Effectiveness Network, 2012-2013 Through 2017-2018.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2021Article
- Simple models to include influenza vaccination history when evaluating the effect of influenza vaccination.Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2021Article
- Vaccine Effectiveness Against Influenza-Associated Hospitalizations Among Adults, 2018-2019, US Hospitalized Adult Influenza Vaccine Effectiveness Network.The Journal of infectious diseases · 2021Article
- Influenza vaccine effectiveness against hospitalizations in children and older adults-Data from South America, 2013-2017. A test negative design.Vaccine: X · 2019Article
- Application of volumetric absorptive microsampling (VAMS) to measure multidimensional anti-influenza IgG antibodies by the mPlex-Flu assay.Journal of clinical and translational science · 2019Article
- Challenges in estimating influenza vaccine effectiveness.Expert review of vaccines · 2019Review
Corrections and comments
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Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundVaccination history may confound estimates of influenza vaccine effectiveness (VE) when two conditions are present: (1) Influenza vaccination is associated with vaccination history and (2) vaccination modifies the risk of natural infection in the following seasons, either due to persisting vaccination immunity or due to lower previous risk of natural infection.
methodsAnalytic arguments are used to define conditions for confounding of VE estimates by vaccination history. Simulation studies, both with accurate and inaccurate assessment of current and previous vaccination status, are used to explore the potential magnitude of these biases when using different statistical models to address confounding by vaccination history.
resultsWe found a potential for substantial bias of VE estimates by vaccination history if infection- and/or vaccination-derived immunity persisted from one season to the next and if vaccination uptake in individuals was seasonally correlated. Full adjustment by vaccination history, which is usually not feasible, resulted in unbiased VE estimates. Partial adjustment, i.e. only by prior season's vaccination status, significantly reduced confounding bias. Misclassification of vaccination status, which can also lead to substantial bias, interferes with the adjustment of VE estimates for vaccination history.
conclusionsConfounding by vaccination history may bias VE estimates, but even partial adjustment by only the prior season's vaccination status substantially reduces confounding bias. Misclassification of vaccination status may compromise VE estimates and efforts to adjust for vaccination history.
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