An international core outcome set for evaluating interventions to improve informed consent to clinical trials: the ELICIT Study

Katie Gillies* (Corresponding Author), Paula R Williamson, Vikki A Entwistle, Heidi Gardner, Shaun Treweek, Marion K Campbell

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)
4 Downloads (Pure)


OBJECTIVE: To develop a core outcome set for the evaluation of interventions that aim to improve how people make decisions about whether to participate in RCTs (of healthcare interventions), the ELICIT Study.

STUDY DESIGN: International mixed-method study involving a systematic review of existing outcomes, semi-structured interviews, an online Delphi survey, and a face-to-face consensus meeting..

RESULTS: The literature review and stakeholder interviews (n=25) initially identified 1045 reported outcomes that were grouped into 40 individually distinct outcomes. These 40 outcomes were scored for importance in two rounds of an online Delphi survey (n=79), with 18 people attending the consensus meeting. Consensus was reached on 12 core outcomes: therapeutic misconception; comfort with decision; authenticity of decision; communication about the trial; empowerment; sense of altruism; equipoise; knowledge; salience of questions; understanding, how helpful the process was for decision making; and trial attrition.

CONCLUSION: The ELICIT core outcome set is the first internationally agreed minimum set of outcomes deemed essential to be measured in all future studies evaluating interventions to improve decisions about participating in an RCT. Use of the ELICIT core set will ensure that results from these trials are comparable and relevant to all stakeholders.


Original languageEnglish
Pages (from-to)14-22
Number of pages9
JournalJournal of Clinical Epidemiology
Early online date26 Feb 2021
Publication statusPublished - Sept 2021

Bibliographical note

Funding: KG was supported by an MRC Methodology Research Fellowship (MR/L01193X/1). The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the MRC. PRW was funded by the MRC North West Hub for Trials Methodology Research (MR/K025635/1) and the MRC/NIHR Trials Methodology Research Partnership (MR/S014357/1). The Health Services Research Unit is core-funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates (CZU/3/3).

Acknowledgements: The ELICIT Study team would like to thank Cynthia Fraser for help with developing and running the search strategies for the literature review, the DelphiManager team for all their support and guidance on the use of the Delphi platform, Health Services Research Unit Patient Involvement Group critical review of the Delphi questionnaire before dissemination, Heather Bagley for further comments on the Delphi questionnaire and also for dissemination of the survey information and link to a range of patient facing organisations, and to Beverley Smith for her assistance in organising the consensus meeting. We would also like to thank all participants of the study (including interview participants, Delphi respondents, and consensus meeting members) and organisations who disseminated the survey.

Data Sharing: Data from the systematic review and Delphi survey phases of work are available from the corresponding author on request.


  • Informed consent
  • clinical trials
  • Core outcome set


Dive into the research topics of 'An international core outcome set for evaluating interventions to improve informed consent to clinical trials: the ELICIT Study'. Together they form a unique fingerprint.

Cite this