Out of sight but not out of mind: how to search for unpublished clinical trial evidence
Open accessAbstract
A key challenge in conducting systematic reviews is to identify the existence and results of unpublished trials, and unreported methods and outcomes within published trials. An-Wen Chan provides guidance for reviewers on adopting a comprehensive strategy to search beyond the published literature
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High quality protocols and statistical analysis plans contain relevant information on study design and conduct that is often not reported in journal publications or trial registries.
“High quality protocols and statistical analysis plans contain relevant information on study design and conduct that is often not reported in journal publications or trial registries.79 80”
From SPIRIT 2025 explanation and elaboration: updated guideline for protocols of randomised trials (2025) · cites this paper as [79]
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- Authors
- Chan, A.-W.
- Affiliations
- University of Toronto (CA)
- Corresponding author
- Chan, A.-W.
- Venue
- BMJ
- Publisher
- BMJ
- Published
- 2012-01-03
- Volume
- 344
- Issue
- jan03 2
- Pages
- d8013-d8013
- ISSN
- 0007-1447 (ISSN-L)
- 0959-8138
- 1468-5833
- OpenAlex
- W2170022337
- Cited by
- 62
- References
- 40
- Citations by year
- 2026: 1 · 2025: 2 · 2023: 2 · 2022: 1 · 2021: 4 · 2020: 5 · 2019: 2 · 2018: 5 · 2017: 7 · 2016: 9 · 2015: 5 · 2014: 3 · 2013: 10 · 2012: 5
- FWCI
- 2.03
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- BMJ (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
- Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Pharmacology › Pharmaceutical industry and healthcare
- Social Sciences › Decision Sciences › Information Systems and Management › Academic Publishing and Open Access
- Keywords
- unpublished clinical trials, clinical trial registries, systematic review search strategy, reporting bias, clinical trial registration
- MeSH terms
- Data Collection, Humans, Periodicals as Topic, Randomized Controlled Trials as Topic, Information Storage and Retrieval, Internet
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