Table 1

Study inclusion and exclusion criteria

Inclusion criteria	Exclusion criteria
Full length, peer-reviewed original studies using the Delphi method with international participants to develop a COS Protocols for studies using international Delphi surveys to develop a COS (may be non-peer-reviewed)	Articles that were not published within the accepted date range: 1 January 2017–6 June 2019 Articles not written in English Articles that were not full-text and peer-reviewed (with the exception of protocol studies) Articles that do not report development of a COS for a medical condition or intervention for the purposes of clinical trial reporting Articles that do not report using a Delphi survey Articles that do not report using an ‘international’ Delphi survey (members of at least one of the following groups should be described as international: patients, patient representatives or healthcare professionals)

Inclusion criteria

Exclusion criteria

Full length, peer-reviewed original studies using the Delphi method with international participants to develop a COS
Protocols for studies using international Delphi surveys to develop a COS (may be non-peer-reviewed)

Articles that were not published within the accepted date range: 1 January 2017–6 June 2019
Articles not written in English
Articles that were not full-text and peer-reviewed (with the exception of protocol studies)
Articles that do not report development of a COS for a medical condition or intervention for the purposes of clinical trial reporting
Articles that do not report using a Delphi survey
Articles that do not report using an ‘international’ Delphi survey (members of at least one of the following groups should be described as international: patients, patient representatives or healthcare professionals)