Methods for conducting international Delphi surveys to optimise global participation in Core Outcome Set development: a case study in gastric cancer informed by a comprehensive literature review.

Bilal Alkhaffaf*, Jane Blazeby, Aleksandra Metryka, Anne Marie Glenny, Ademola Adeyeye, Paulo Matos Costa, Ismael Diez del Val, Suzanne S Gisbertz, Ali Guner, Simon Law, Hyuk-Joon Lee, Ziyu Li, Koji Nakada, Rafael Mauricio Restrepo Nunez, Daniel Reim, John V Reynolds, Peter Vorwald, Daniela Zanotti, William H Allum, M Asif ChaudryEwen Griffiths, Paula R Williamson, Iain A. Bruce

*Corresponding author for this work

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Core outcome sets (COS) should be relevant to key stakeholders, and widely applicable and usable. Ideally, they are developed for international use to allow optimal data synthesis from trials. Electronic Delphi surveys are commonly used to facilitate global participation; however, this has limitations. It is common for these surveys to be conducted in a single language potentially excluding those not fluent in that tongue. The aim of this study is to summarise current approaches for optimising international participation in Delphi studies and make recommendations for future practice.
A comprehensive literature review of current approaches to translating Delphi surveys for COS development was undertaken. A standardised methodology adapted from international guidance derived from 12 major sets of translation guidelines in the field of outcomes reporting was developed. As a case study this was applied to a COS project for surgical trials in gastric cancer to translate a Delphi survey into 7 target languages from regions active in gastric cancer research.
332 abstracts were screened and four studies addressing COS development in rheumatoid and osteo-arthritis, vascular malformations and polypharmacy were eligible for inclusion. There was wide variation in methodological approaches to translation, including the number of forward translations, the inclusion of back translation, the employment of cognitive debriefing and how discrepancies and disagreements were handled. Important considerations were identified during the development of the gastric cancer survey including establishing translation groups, timelines, understanding financial implications, strategies to maximise recruitment and regulatory approvals. The methodological approach to translating the Delphi surveys were easily reproducible by local collaborators and resulted in an additional 637 participants to the 315 recruited to complete the source language survey. 99% of patients and 97% of healthcare professionals from non-English speaking regions used translated surveys.
Consideration of the issues described will improve planning by other COS developers and can be used to widen international participation from both patients and healthcare professionals.
Original languageEnglish
Article number410
JournalBritish Journal of Surgery
Issue number1
Early online date21 Jun 2021
Publication statusPublished - Dec 2021

Bibliographical note

Funding Information:
The authors would like to highlight the role undertaken by Dr Aleksandra Metryka, Senior Clinical Trials Coordinator, who facilitated the running of this study. In addition, the authors would like to thank the following associations and groups for their support in facilitating recruitment to the GASTROS study Delphi survey: ? The International Gastric Cancer Association ( ? The Association of Upper Gastro-Intestinal Surgeons of Great Britain and Ireland ( ? The Brazilian Gastric Cancer Association ( ? The Canadian Gastric Cancer Association ( ? The Chinese Gastric Cancer Association ? The Dutch Upper GI Cancer Group ( ? The GASTRODATA group ( ? Italian Research Group for Gastric Cancer ( ? The Korean Gastric Cancer Association ( ? Oesophago-Gastric Surgery Section of the Asociaci?n Espa?ola de Cirujanos ? Spain ( ? Upper GI International Robotic Association ( ? United Kingdom Oncology Nursing Society ( ? The European Oncology Nursing Society ( ? The Oesophageal Patients Association ? UK ( ? My Gut Feeling ? Canada ( ? No Stomach for Cancer ? USA ( ? Vivere Senza Stomaco - Italy () ? Gastro/Oesophageal Support and Help Cancer Group (Bristol) ? UK ? The Greater Manchester Oesophago-gastric patient support group ? UK GASTROS International Working Group Collaborators (to be cited as collaborators in PUBMED) ? Shuangxi Li ? Yu-long He ? Zekuan Xu ? Yingwei Xue ? Han Liang ? Guoxin Li ? Enhao Zhao ? Philipp Neumann ? Linda O?Neill ? Emer Guinan ? Gian Luca Baiocchi ? Giovanni de Manzoni ? Eliza R.C. Hagens ? Mark I. van Berge Henegouwen ? Patr?cia Lages ? Susana Onofre ? Gabriel Salcedo Caba?as ? Maria Posada Gonzalez ? Cristina Marin Campos ? Bahar Candas ? Bahad?r Emre Baki ? Muhammed Selim Bodur ? Reyyan Yildirim ? Arif Burak Cekic ? Jean-Baptiste Beuscart ? Sophie Horbach ? Christopher Mecoli ? Toby O Smith

Funding Information:
This study is funded by the National Institute for Health Research (NIHR) Doctoral Research Fellowship Grant (DRF-2015-08-023). JMB is partially funded by the NIHR Bristol Biomedical Research Centre and the MRC ConDUCT-II Hub for Trials Methodology Research. PRW was funded by the MRC North West Hub for Trials Methodology Research (Grant ref: MR/K025635/01).

Publisher Copyright:
© 2021, The Author(s).


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