ReviewJournal of epidemiology and community health2002
Confounding by indication in non-experimental evaluation of vaccine effectiveness: the example of prevention of influenza complications.
Review in Journal of epidemiology and community health, 2002. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 43 papers, 2 of them syntheses that pooled it.
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.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
43 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Frequency and impact of confounding by indication and healthy vaccinee bias in observational studies assessing influenza vaccine effectiveness: a systematic review.BMC infectious diseases · 2015Pooled it
- Vaccines for the prevention of seasonal influenza in patients with diabetes: systematic review and meta-analysis.BMC medicine · 2015Pooled it
- Mortality in members of HIV-1 serodiscordant couples in Africa and implications for antiretroviral therapy initiation: results of analyses from a multicenter randomized trial.BMC infectious diseases · 2012Trial
- Effectiveness of adjuvanted influenza vaccination in elderly subjects in northern Italy.American journal of epidemiology · 2012Trial
- The effectiveness of COVID-19 vaccines and the added benefit of booster doses in Hessen, Germany, during the COVID-19 pandemic: Results from a vaccinated-only study.Human vaccines & immunotherapeutics · 2026Article
- Unmeasured confounding and misclassification in studies estimating vaccine effectiveness against hospitalisation and death using electronic health records (EHRs): an evaluation of a multi-country European retrospective cohort study.BMC medical research methodology · 2025Article
- Development of Real-Time Surveillance for Serious Adverse Events in a Pragmatic Clinical Trial Using National Registers in Finland.Clinical epidemiology · 2024Article
- Learning healthcare systems in cardiology: A qualitative interview study on ethical dilemmas of a learning healthcare system.Learning health systems · 2024Article
- Current Approaches to Vaccine Safety Using Observational Data: A Rationale for the EUMAEUS (Evaluating Use of Methods for Adverse Events Under Surveillance-for Vaccines) Study Design.Frontiers in pharmacology · 2022Review
- PICK-ing Malaysia's Epidemic Apart: Effectiveness of a Diverse COVID-19 Vaccine Portfolio.Vaccines · 2021Article
- Assessment of Effectiveness of 1 Dose of BNT162b2 Vaccine for SARS-CoV-2 Infection 13 to 24 Days After Immunization.JAMA network open · 2021Article
- Determinants of vaccination uptake, and influenza vaccine effectiveness in preventing deaths and hospital admissions in the elderly population; Treviso, Italy, 2014/2015-2016/2017 seasons.Human vaccines & immunotherapeutics · 2020Article
- A Community-Based Intervention for Improving Medication Adherence for Elderly Patients with Hypertension in Korea.International journal of environmental research and public health · 2019Article
- External adjustment of unmeasured confounders in a case-control study of benzodiazepine use and cancer risk.British journal of clinical pharmacology · 2017Article
- Effectiveness of seasonal influenza vaccination in patients with diabetes: protocol for a nested case-control study.BMJ open · 2017Article
- Risk-adjusted procedure tailoring leads to uniformly low complication rates in ventral and incisional hernia repair: a propensity score analysis and internal validation of classification criteria.Hernia : the journal of hernias and abdominal wall surgery · 2017Article
- Do influenza and pneumococcal vaccines prevent community-acquired respiratory infections among older people with diabetes and does this vary by chronic kidney disease? A cohort study using electronic health records.BMJ open diabetes research & care · 2017Article
- Longitudinal Trends in Hypertension Management and Mortality Among Octogenarians: Prospective Cohort Study.Hypertension (Dallas, Tex. : 1979) · 2016Article
- Article
- Methodological challenges in measuring vaccine effectiveness using population cohorts in low resource settings.Vaccine · 2015Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Randomised allocation of vaccine or placebo is the preferred method to assess the effects of the vaccine on clinical outcomes relevant to the individual patient. In the absence of phase 3 trials using clinical end points, notably post-influenza complications, alternative non-experimental designs to evaluate vaccine effects or safety are often used. The application of these designs may, however, lead to invalid estimates of vaccine effectiveness or safety. As patients with poor prognosis are more likely to be immunised, selection for vaccination is confounded by patient factors that are also related to clinical end points. This paper describes several design and analytical methods aimed at limiting or preventing this confounding by indication in non-experimental studies. In short, comparison of study groups with similar prognosis, restriction of the study population, and statistical adjustment for dissimilarities in prognosis are important tools and should be considered. Only if the investigator is able to show that confounding by indication is sufficiently controlled for, results of a non-experimental study may be of use to direct an evidence based vaccine policy.
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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.