Core Outcome Set-STAndards for Development: The COS-STAD recommendations
Open accessAbstract
BACKGROUND: The use of core outcome sets (COS) ensures that researchers measure and report those outcomes that are most likely to be relevant to users of their research. Several hundred COS projects have been systematically identified to date, but there has been no formal quality assessment of these studies. The Core Outcome Set-STAndards for Development (COS-STAD) project aimed to identify minimum standards for the design of a COS study agreed upon by an international group, while other specific guidance exists for the final reporting of COS development studies (Core Outcome Set-STAndards for Reporting [COS-STAR]). METHODS AND FINDINGS: An international group of experienced COS developers, methodologists, journal editors, potential users of COS (clinical trialists, systematic reviewers, and clinical guideline developers), and patient representatives produced the COS-STAD recommendations to help improve the quality of COS development and support the assessment of whether a COS had been developed using a reasonable approach. An open survey of experts generated an initial list of items, which was refined by a 2-round Delphi survey involving nearly 250 participants representing key stakeholder groups. Participants assigned importance ratings for each item using a 1-9 scale. Consensus that an item should be included in the set of minimum standards was defined as at least 70% of the voting participants from each stakeholder group providing a score between 7 and 9. The Delphi survey was followed by a consensus discussion with the study management group representing multiple stakeholder groups. COS-STAD contains 11 minimum standards that are the minimum design recommendations for all COS development projects. The recommendations focus on 3 key domains: the scope, the stakeholders, and the consensus process. CONCLUSIONS: The COS-STAD project has established 11 minimum standards to be followed by COS developers when planning their projects and by users when deciding whether a COS has been developed using reasonable methods.
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The present study was registered with the COMET Initiative (No. 3559) and reported following the COS-STAR Statement.
“The present study was registered with the COMET Initiative (No. 3559 accessible at https://www.comet‐initiative.org/Studies/Details/3559) and reported following the Core Outcome Set–STAndards for Reporting (COS‐STAR) Statement (Kirkham et al. 2017).”
From 1st Global Consensus for Clinical Guidelines: Identifying a Core Outcome Set for Implant Dentistry in Edentulous Maxilla Rehabilitation (2026) · cites this paper as Kirkham et al. 2017
The Discussion identifies COS-STAR as guidance for reporting core outcome set studies. But the cited paper is the COS-STAD development recommendations, not the COS-STAR Statement; its References identify the latter as a separate 2016 paper. It also does not establish that the citing study was registered as COMET No. 3559 or followed COS-STAR. (LLM, conf=0.86)
Experimental — accuracy not yet measuredAssessing the quality of the identified COS remains challenging.
“First, although a COS for the edentulous maxilla was identified, assessing its quality remains challenging (Kirkham et al. 2017).”
From 1st Global Consensus for Clinical Guidelines: Identifying a Core Outcome Set for Implant Dentistry in Edentulous Maxilla Rehabilitation (2026) · cites this paper as Kirkham et al. 2017
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Cites
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Butcher, N. J., Monsour, A., Mew, E. J., Chan, A.-W., Moher, D., Mayo-Wilson, E., Terwee, C. B., Chee-A-Tow, A., Baba, A., Gavin, F., et al. (2022) · JAMA · doi:10.1001/jama.2022.21243 · Cited by 288 · see citing works
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“The present study was registered with the COMET Initiative (No. 3559 accessible at https:// www. comet - initi ative. org/ Studi es/ Detai ls/ 3559) and reported following the Core Outcome Set–STAndards for Reporting (COS-STAR) Statement (Kirkham et al. 2017).”
- Authors
- Kirkham, J. J., Davis, K., Altman, D. G., Blazeby, J. M., Clarke, M., Tunis, S., & Williamson, P. R.
- Affiliations
- University of Liverpool (GB)
- University of Oxford (GB)
- University of Bristol (GB)
- Queen's University Belfast (GB)
- Center for Medical Technology Policy (US)
- Corresponding author
- Williamson, Paula R.
- ORCID
- Venue
- PLOS Medicine
- Publisher
- Public Library of Science (PLoS)
- Published
- 2017-11-16
- Volume
- 14
- Issue
- 11
- Pages
- e1002447
- ISSN
- 1549-1277 (ISSN-L)
- 1549-1676
- PMC
- PMC5689835
- OpenAlex
- W2770677162
- Cited by
- 792
- References
- 3
- Citations by year
- 2026: 109 · 2025: 125 · 2024: 94 · 2023: 89 · 2022: 105 · 2021: 115 · 2020: 88 · 2019: 46 · 2018: 19 · 2017: 1
- FWCI
- 107.86
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- PLoS Medicine (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Research Explorer (The University of Manchester) (publishedVersion, other-oa)
- Bristol Research (University of Bristol) (submittedVersion, cc-by)
- RePEc: Research Papers in Economics (submittedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Figshare (submittedVersion, cc-by)
- Research Portal (Queen's University Belfast) (submittedVersion, cc-by)
- Explore Bristol Research (submittedVersion, cc-by)
- Funders
- Cincinnati Children's Hospital Medical Center
- National Institute for Health and Care Excellence
- Cancer Research UK (16895)
- National Institute for Health and Care Research (NF-SI-0513-10025)
- University of Warwick
- University of Bath
- University of Bristol
- Medical Research Council (MR/L004933/1, MR/L004933/2)
- Topics
- Social Sciences › Sociology and Political Science › Delphi Technique in Research
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Clinical practice guidelines implementation
- Keywords
- core outcome set, minimum standards, Delphi consensus, stakeholder engagement, outcome measurement, patient representatives
- MeSH terms
- Delphi Technique, Humans, Surveys and Questionnaires, Research Design, Outcome Assessment, Health Care, Endpoint Determination
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