Cited by 207Meta-analysis and systematic reviewsStatistical Methods in Clinical TrialsStatistical Methods in Epidemiology

Catalogue of bias: attrition bias

Nunan, David, Aronson, Jeffrey, Bankhead, Clare·2018·BMJ Evidence-Based Medicine

Abstract

This article is part of a series of articles featuring the Catalogue of Bias introduced in this volume of BMJ Evidence-Based Medicine that describes attrition bias and outlines its potential impact on research studies and the preventive steps to minimise its risk. Attrition bias is a type of selection bias due to systematic differences between study groups in the number and the way participants are lost from a study. Differences between people who leave a study and those who continue, particularly between study groups, can be the reason for any observed effect and not the intervention itself. Associations for mortality in trials of tranexamic acid and upper gastrointestinal bleeding were no longer apparent after studies with high or unclear risk of attrition bias were removed. Over-recruitment can help prevent important attrition bias. Sampling weights and tailored replenishment samples can help to compensate for the effects of attrition bias when present.

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Crossref · 10.1136/ebmed-2017-110883

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Authors
Nunan, D., Aronson, J., & Bankhead, C.
Affiliations
University of Oxford (GB)
Venue
BMJ Evidence-Based Medicine
Publisher
BMJ
Published
2018-01-24
Volume
23
Issue
1
Pages
21-22
ISSN
  • 1356-5524 (ISSN-L)
  • 2515-446X
  • 2515-4478
OpenAlex
W2784801669
Cited by
204
References
9
Citations by year
2026: 25 · 2025: 36 · 2024: 32 · 2023: 27 · 2022: 39 · 2021: 24 · 2020: 15 · 2019: 6
FWCI
8.58
Type
journal article
Language
en
Open access
closed
Locations
  • BMJ Evidence-Based Medicine (publishedVersion)
  • PubMed (publishedVersion)
  • HighWire Press Open Archive (submittedVersion)
Topics
  • Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
Keywords
attrition bias, selection bias, participant dropout, trial bias, sampling weights, tranexamic acid, upper gastrointestinal bleeding, mortality
MeSH terms
Humans, Patient Dropouts, Bias, Selection Bias

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