ArticleEmerging themes in epidemiology2008
Simpson's Paradox, Lord's Paradox, and Suppression Effects are the same phenomenon--the reversal paradox.
Article in Emerging themes in epidemiology, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 92 papers, 2 of them syntheses that pooled it.
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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
92 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Severely malnourished children with a low weight-for-height have similar mortality to those with a low mid-upper-arm-circumference: II. Systematic literature review and meta-analysis.Nutrition journal · 2018Pooled it
- Country of birth and hospital treatment for psychosis in New South Wales.Social psychiatry and psychiatric epidemiology · 2013Pooled it
- Marital Conflict Predicts Mother-to-Infant Adrenocortical Transmission.Child development · 2019Trial
- Nasopharyngeal carriage and macrolide resistance in Indigenous children with bronchiectasis randomized to long-term azithromycin or placebo.European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology · 2015Trial
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- Social Connectedness Buffering the Interaction Between Problematic Internet Use and Psychopathological Symptoms Among Adolescents: Undirected and Bayesian Network Analyses.Journal of medical Internet research · 2026Article
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- Knowledge, Attitudes, Practices, and Information Pathways Related to Brucellosis Among Adults in Najran City, Saudi Arabia: A Stratified Time-Location Cross-Sectional Study.Tropical medicine and infectious disease · 2026Article
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- Prevalence of head lice infestation and its associated factors in primary school students in Shiraz City, Fars Province, Iran.BMC public health · 2026Article
- Global Patterns, Temporal Trends, and Potential Non-Infectious Risk Factors for Burkitt Lymphoma from 1990 to 2021.Blood and lymphatic cancer : targets and therapy · 2026Article
- Identification of multivariable predictors for prediabetes: biochemical integration and pathophysiological mechanism analysis based on health examination data.Frontiers in endocrinology · 2026Article
- Lord's Paradox and two network meta-analysis models.Research synthesis methods · 2026Article
- Weighted quantile sum (WQS) mixed-effects model.MethodsX · 2025Article
- Diagnostic criteria for severe acute malnutrition and fatal outcomes in children aged 6-59 months, Nigeria.Bulletin of the World Health Organization · 2025Observational
- The Evidence-Based Medicine Management of Endometriosis Should Be Updated for the Limitations of Trial Evidence, the Multivariability of Decisions, Collective Experience, Heuristics, and Bayesian Thinking.Journal of clinical medicine · 2025Article
- Identifying primary-care features associated with complex mental health difficulties.PloS one · 2025Article
32 more citing papers are in PubMed but not listed here.
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Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
This article discusses three statistical paradoxes that pervade epidemiological research: Simpson's paradox, Lord's paradox, and suppression. These paradoxes have important implications for the interpretation of evidence from observational studies. This article uses hypothetical scenarios to illustrate how the three paradoxes are different manifestations of one phenomenon--the reversal paradox--depending on whether the outcome and explanatory variables are categorical, continuous or a combination of both; this renders the issues and remedies for any one to be similar for all three. Although the three statistical paradoxes occur in different types of variables, they share the same characteristic: the association between two variables can be reversed, diminished, or enhanced when another variable is statistically controlled for. Understanding the concepts and theory behind these paradoxes provides insights into some controversial or contradictory research findings. These paradoxes show that prior knowledge and underlying causal theory play an important role in the statistical modelling of epidemiological data, where incorrect use of statistical models might produce consistent, replicable, yet erroneous results.
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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.