Clinician-trialist rounds: 5. Cointervention bias – how to diagnose it in their trial and prevent it in yours
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Bias can arise when the trial groups receive different concomitant care-for example, additional interventions that may affect trial outcomes.
“Bias can arise when the trial groups receive different concomitant care—for example, additional interventions that may affect trial outcomes.246”
From SPIRIT 2025 explanation and elaboration: updated guideline for protocols of randomised trials (2025) · cites this paper as [246]
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“Secondary intervention bias or co-intervention bias can occur in trials where additional treatment decisions and interventions are performed after the initial randomization 6 .”
- Authors
- Sackett, D. L.
- Affiliations
- Trout Research & Education Centre at Irish Lake, RR 1, Markdale, Ontario, Canada, N0C 1H0
- Corresponding author
- Sackett, David L
- Venue
- Clinical Trials
- Publisher
- SAGE Publications
- Published
- 2011-08
- Volume
- 8
- Issue
- 4
- Pages
- 440-442
- ISSN
- 1740-7745 (ISSN-L)
- 1740-7753
- OpenAlex
- W2051682833
- Cited by
- 32
- References
- 5
- Citations by year
- 2026: 2 · 2025: 5 · 2024: 1 · 2023: 4 · 2022: 3 · 2021: 5 · 2020: 2 · 2019: 2 · 2018: 1 · 2017: 1 · 2016: 2 · 2013: 3
- FWCI
- 1.37
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Clinical Trials (publishedVersion)
- PubMed (publishedVersion)
- 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 › Advanced Causal Inference Techniques
- Keywords
- trial design, bias detection, bias prevention, confounding
- MeSH terms
- Data Interpretation, Statistical, Humans, Risk, Bias, Controlled Clinical Trials as Topic
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