ArticleEpidemiology (Cambridge, Mass.)2022
Toward a Clearer Definition of Selection Bias When Estimating Causal Effects.
Article in Epidemiology (Cambridge, Mass.), 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 106 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
106 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- The Same but Different?: A Systematic Review of the Impact of Selection and Collider Bias on Internal Validity.Epidemiology (Cambridge, Mass.) · 2025Pooled it
- Use of sensitivity analyses to assess uncontrolled confounding from unmeasured variables in observational, active comparator pharmacoepidemiologic studies: a systematic review.American journal of epidemiology · 2025Pooled it
- Early-life liquefied petroleum gas cooking intervention and lung function in Guatemalan children: a randomized clinical trial.Annals of the American Thoracic Society · 2026Trial
- The effect of fetal movement awareness on birth outcomes among Somali migrant women - findings from a non-randomised intervention study in Sweden.BMC pregnancy and childbirth · 2026Trial
- CT changes in a randomized trial comparing early therapies in an outpatient population at high risk of severe COVID19 disease.Scientific reports · 2025Trial
- Effect of a pay-it-forward strategy on reducing HPV vaccine delay and increasing uptake among 15- to 18-year-old girls in China: A randomized controlled trial.PLoS medicine · 2025Trial
- Pay-it-forward incentives for hepatitis virus testing in men who have sex with men: a cluster randomized trial.Nature medicine · 2023Trial
- Choosing real-world data for clinical and epidemiological research: methodological lessons from NHIRD and TriNetX-A narrative review.Annals of medicine · 2026Review
- Community-level disaster exposure and attrition in a longitudinal cohort study: Implications for aging research.Annals of epidemiology · 2026Article
- Nonrandom Selection With and Without Bias Due to Selecting on an Exposure.Epidemiology (Cambridge, Mass.) · 2026Article
- Comments on "Reassessing Small Intestinal Bacterial Overgrowth in Irritable Bowel Syndrome: A Comparative Study of Diagnostic Guidelines and Their Clinical Relevance".Journal of gastroenterology and hepatology · 2026Article
- Using Negative Control Outcomes to Detect Selection Bias in Mendelian Randomization Studies.Statistics in medicine · 2026Article
- Extrapolating Vincristine-Induced Peripheral Neuropathy From Caucasian to Kenyan Populations: Impact of Type I and Type II Selection Bias.CPT: pharmacometrics & systems pharmacology · 2026Article
- Causal Inference in Clinical Research: A Primer.Journal of periodontal research · 2026Review
- Methods for incorporating test result information within the high-dimensional propensity score framework: application in UK electronic health record data.BMC medical research methodology · 2026Article
- A Cross-sectional Study on Quality of Life in EB: Validation of the Italian QOLEB and Assessment in Italian Patients.Acta dermato-venereologica · 2026Article
- Quantifying and adjusting for selection biases in the Norwegian Mother, Father and Child Cohort Study using population-wide individual-level registry information.International journal of epidemiology · 2026Article
- Survival as a source of confounding, selection bias, and effect modification.International journal of epidemiology · 2026Article
- Pregnancy identification method as a source of bias in studies of prenatal exposures using real-world data.American journal of epidemiology · 2026Article
- Prompt and Intensive Antiviral Chemoprophylaxis in Nursing Home Influenza Outbreaks.JAMA internal medicine · 2026Article
46 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.
Funding
Abstract
Selection bias remains a subject of controversy. Existing definitions of selection bias are ambiguous. To improve communication and the conduct of epidemiologic research focused on estimating causal effects, we propose to unify the various existing definitions of selection bias in the literature by considering any bias away from the true causal effect in the referent population (the population before the selection process), due to selecting the sample from the referent population, as selection bias. Given this unified definition, selection bias can be further categorized into two broad types: type 1 selection bias owing to restricting to one or more level(s) of a collider (or a descendant of a collider) and type 2 selection bias owing to restricting to one or more level(s) of an effect measure modifier. To aid in explaining these two types-which can co-occur-we start by reviewing the concepts of the target population, the study sample, and the analytic sample. Then, we illustrate both types of selection bias using causal diagrams. In addition, we explore the differences between these two types of selection bias, and describe methods to minimize selection bias. Finally, we use an example of "M-bias" to demonstrate the advantage of classifying selection bias into these two types.
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Registered trials
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.