ArticleClinical infectious diseases : an official publication of the Infectious Diseases Society of America2022
Effects of Confounding Bias in Coronavirus Disease 2019 (COVID-19) and Influenza Vaccine Effectiveness Test-Negative Designs Due to Correlated Influenza and COVID-19 Vaccination Behaviors.
Article in Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 89 papers.
What it found
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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.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
89 citing papers in PubMed, 112 citations in OpenAlex.
- Validating and leveraging non-SARS-CoV-2 respiratory infection as a negative control outcome in a phase 3 COVID-19 vaccine trial with extended observational follow-up.American journal of epidemiology · 2026Trial
- Bivalent RSVpreF Effectiveness Against Respiratory Syncytial Virus (RSV)-Related Respiratory Disease Hospitalization and Emergency Department Visits Across Three RSV Seasons.Infectious diseases and therapy · 2026Article
- Influenza Vaccine Effectiveness Against Influenza-Associated Hospitalizations and Emergency Department or Urgent Care Encounters Among Children and Adults-VISION, United States, 2024-2025 Season.Open forum infectious diseases · 2026Article
- Bivalent RSVpreF effectiveness against RSV-associated hospital or emergency department care over two seasons: a retrospective test-negative case control study.Lancet regional health. Americas · 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
- Considerations for assessing the feasibility of network meta-analysis of seasonal vaccines.Journal of comparative effectiveness research · 2026Article
- Influenza Vaccination Effectiveness Against Influenza-Associated Hospitalization in Children and the Effects of Repeated Vaccination.The Journal of infectious diseases · 2026Article
- Influenza Vaccine and Associated Infection and Death in California, 2024 to 2025.JAMA network open · 2026Article
- Interim 2025/26 LP.8.1 vaccine effectiveness estimates against COVID-19 from the Canadian Sentinel Practitioner Surveillance Network (SPSN): insights into possible impact of influenza and other respiratory virus co-circulation.Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2026Article
- Influenza vaccine effectiveness against influenza-associated hospitalizations and emergency department or urgent care encounters among children and adults - United States, 2024-25 season.medRxiv : the preprint server for health sciences · 2026Article
- Article
- 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 of Updated 2023-2024 (Monovalent XBB.1.5) COVID-19 Vaccination Against SARS-CoV-2 Omicron XBB and BA.2.86/JN.1 Lineage Hospitalization and a Comparison of Clinical Severity-IVY Network, 26 Hospitals, 18 October 2023-9 March 2024.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2026Article
- Interim Estimates of 2025-26 Seasonal Influenza Vaccine Effectiveness - United States, September 2025-February 2026.MMWR. Morbidity and mortality weekly report · 2026Article
- Effectiveness of 2024/25 KP.2 Vaccine Against Outpatient COVID-19 in Canada.Influenza and other respiratory viruses · 2026Article
- Influenza Vaccine Effectiveness Against Influenza A(H1N1)pdm09-Associated Hospitalizations With SARI in Beijing, China, in the 2024-2025 Season.Influenza and other respiratory viruses · 2026Article
- Estimated Vaccine Effectiveness for Respiratory Syncytial Virus-Related Acute Respiratory Illness in Older Adults: Findings From the First Postlicensure Season.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2026Article
- Estimated Effectiveness of 2024-2025 COVID-19 Vaccination Against Severe COVID-19.JAMA network open · 2026Article
- Article
- COVID-19 vaccine effectiveness in preventing severe outcomes and assessing the impact of prior SARS-CoV-2 infection among hospitalized adults in Albania, July 2022-July 2023.PLOS global public health · 2026Article
29 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe test-negative design is commonly used to estimate influenza and coronavirus disease 2019 (COVID-19) vaccine effectiveness (VE). In these studies, correlated COVID-19 and influenza vaccine behaviors may introduce a confounding bias where controls are included with the other vaccine-preventable acute respiratory illness (ARI). We quantified the impact of this bias on VE estimates in studies where this bias is not addressed.
methodsWe simulated study populations under varying vaccination probabilities, COVID-19 VE, influenza VE, and proportions of controls included with the other vaccine-preventable ARI. Mean bias was calculated as the difference between estimated and true VE. Absolute mean bias in VE estimates was classified as low (<10%), moderate (10% to <20%), and high (≥20%).
resultsWhere vaccination probabilities are positively correlated, COVID-19 and influenza VE test-negative studies with influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ARI controls, respectively, underestimate VE. For COVID-19 VE studies, mean bias was low for all scenarios where influenza represented ≤25% of controls. For influenza VE studies, mean bias was low for all scenarios where SARS-CoV-2 represented ≤10% of controls. Although bias was driven by the conditional probability of vaccination, low VE of the vaccine of interest and high VE of the confounding vaccine increase its magnitude.
conclusionsWhere a low percentage of controls is included with the other vaccine-preventable ARI, bias in COVID-19 and influenza VE estimates is low. However, influenza VE estimates are likely more susceptible to bias. Researchers should consider potential bias and its implications in their respective study settings to make informed methodological decisions in test-negative VE studies.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.