Reporting of randomised factorial trials: development of extensions to the CONSORT 2010 and SPIRIT 2013 guidance statements
Lead Research Organisation:
University of Nottingham
Department Name: School of Medicine
Abstract
CONTEXT
Randomised trials provide the strongest evidence available about the effectiveness of health care interventions. Standards exist for reporting randomised trials so that users of evidence may clearly see strengths or deficiencies in study design or conduct that could affect the validity of the results. Widely adopted and evidence-based, SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) and CONSORT (Consolidated Standards of Reporting Trials) statements provide minimum recommendations for reporting protocols and results of randomised trials.
Factorial randomised trials represent the potential for efficient evaluation of more than one intervention in the same study without the need for a larger sample size. In its simplest 2x2 form to test two interventions (A and B), participants are randomised to receive either no intervention, A alone, B alone or both A and B. Factorial trials have specific design and analysis considerations in addition to standard items specified in SPIRIT and CONSORT guidance. While extensions to SPIRIT and CONSORT exist for methodological variations, including different trial designs, interventions and types of data, extensions do not yet exist for factorial trials.
AIM
The aim of this study is to develop extensions for reporting factorial randomised trials to the SPIRIT and CONSORT statements.
METHODS
We will adopt similar methods as used previously to develop SPIRIT and CONSORT main statements and extensions. We will first conduct a scoping review of the literature to draw up a long list of items that we consider may be useful in reporting factorial trials. The scoping review will be completed prior to starting the present study and does not form part of the request for funding, but is included here for completeness.
We will then conduct a Delphi study comprising (1) an online survey, and (2) a consensus meeting. For the online survey, we will contact stakeholders including clinical trials researchers with experience in the design/conduct/analysis/reporting of factorial trials, knowledge users, representatives from funding bodies, journal editors, and PPI (patient and public involvement) representatives. We will identify individuals from relevant publications and through research networks such as the MRC-NIHR Trials Methodology Research Partnership.
As there is no formal method for estimating required sample size for a Delphi survey, we will aim to recruit the largest sample in the time available. Previous experience suggests that up to 130 individuals will be invited. Participants will be asked to complete two survey rounds in which they indicate importance of including items identified in the scoping review in a final list. They can also suggest new items in round 1. In round 2, they are presented with their own score from round 1 as well as summary scores from other participants. After survey round 2, we will use pre-defined criteria to define each item as 'consensus in', 'consensus out', or 'no consensus'.
Following the survey, items defined as 'consensus out' will be discarded and all others will be taken forward for discussion at a consensus meeting. Participants at the meeting (approximately 30) will comprise stakeholders represented in the survey. Each item will be discussed and voted on for inclusion in the final list of items for SPIRIT and CONSORT extension.
The final phase of the study involves writing and disseminating SPIRIT and CONSORT extension guidance and checklists, and a shared Explanation and Elaboration document.
BENEFITS
The outputs of this research will provide investigators with a comprehensive framework for the design, conduct, analysis, interpretation and dissemination of factorial randomised trials. CONSORT and SPIRIT extensions will aid in critical appraisal and interpretation for grant reviewers, funding bodies, trial methodologists, journal editors, reviewers, and readers.
Randomised trials provide the strongest evidence available about the effectiveness of health care interventions. Standards exist for reporting randomised trials so that users of evidence may clearly see strengths or deficiencies in study design or conduct that could affect the validity of the results. Widely adopted and evidence-based, SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) and CONSORT (Consolidated Standards of Reporting Trials) statements provide minimum recommendations for reporting protocols and results of randomised trials.
Factorial randomised trials represent the potential for efficient evaluation of more than one intervention in the same study without the need for a larger sample size. In its simplest 2x2 form to test two interventions (A and B), participants are randomised to receive either no intervention, A alone, B alone or both A and B. Factorial trials have specific design and analysis considerations in addition to standard items specified in SPIRIT and CONSORT guidance. While extensions to SPIRIT and CONSORT exist for methodological variations, including different trial designs, interventions and types of data, extensions do not yet exist for factorial trials.
AIM
The aim of this study is to develop extensions for reporting factorial randomised trials to the SPIRIT and CONSORT statements.
METHODS
We will adopt similar methods as used previously to develop SPIRIT and CONSORT main statements and extensions. We will first conduct a scoping review of the literature to draw up a long list of items that we consider may be useful in reporting factorial trials. The scoping review will be completed prior to starting the present study and does not form part of the request for funding, but is included here for completeness.
We will then conduct a Delphi study comprising (1) an online survey, and (2) a consensus meeting. For the online survey, we will contact stakeholders including clinical trials researchers with experience in the design/conduct/analysis/reporting of factorial trials, knowledge users, representatives from funding bodies, journal editors, and PPI (patient and public involvement) representatives. We will identify individuals from relevant publications and through research networks such as the MRC-NIHR Trials Methodology Research Partnership.
As there is no formal method for estimating required sample size for a Delphi survey, we will aim to recruit the largest sample in the time available. Previous experience suggests that up to 130 individuals will be invited. Participants will be asked to complete two survey rounds in which they indicate importance of including items identified in the scoping review in a final list. They can also suggest new items in round 1. In round 2, they are presented with their own score from round 1 as well as summary scores from other participants. After survey round 2, we will use pre-defined criteria to define each item as 'consensus in', 'consensus out', or 'no consensus'.
Following the survey, items defined as 'consensus out' will be discarded and all others will be taken forward for discussion at a consensus meeting. Participants at the meeting (approximately 30) will comprise stakeholders represented in the survey. Each item will be discussed and voted on for inclusion in the final list of items for SPIRIT and CONSORT extension.
The final phase of the study involves writing and disseminating SPIRIT and CONSORT extension guidance and checklists, and a shared Explanation and Elaboration document.
BENEFITS
The outputs of this research will provide investigators with a comprehensive framework for the design, conduct, analysis, interpretation and dissemination of factorial randomised trials. CONSORT and SPIRIT extensions will aid in critical appraisal and interpretation for grant reviewers, funding bodies, trial methodologists, journal editors, reviewers, and readers.
Technical Summary
Reporting standards for protocols (SPIRIT) and results (CONSORT) of randomised trials improve completeness and transparency of research. Randomised factorial trials require additional methodological complexity in design and analysis not included in standard SPIRIT and CONSORT statements.
This study aim is to improve reporting of randomised factorial trials by developing extensions to CONSORT and SPIRIT statements. We will: (1) complete a scoping review of the literature; (2) conduct an online Delphi survey and (3) consensus meeting of stakeholders including trials researchers, knowledge users, research funders, journal editors, and PPI (patient and public involvement) representatives; (4) produce and disseminating extension checklists and associated explanatory documents.
We aim to complete the scoping review by end of 2020, prior to commencing funding for this study. The output from the review will be a list of items (approximately 40) related to reporting design, conduct and analysis of factorial trials. Phase 2 of the study is an online Delphi survey. Participants will rate importance of each item on the provisional list for inclusion in guidance statements. We anticipate inviting around 100-130 participants. We will conduct two survey rounds. In round 2, participants will see their own round 1 responses and a summary of all other participants' responses. Following completion of round 2, items will be categorised as 'consensus in', 'consensus out' or 'no consensus'.
'Consensus out' items will be discarded and all other items taken forward to a consensus meeting of around 30 participants. Each item will be presented and voted on for inclusion in final checklists for SPIRIT and CONSORT extensions for factorial trials.
We will produce and disseminate the extensions and supporting materials widely through publication, presentation at conferences and workshops, and free availability on the Equator Network and CONSORT and SPIRIT websites.
This study aim is to improve reporting of randomised factorial trials by developing extensions to CONSORT and SPIRIT statements. We will: (1) complete a scoping review of the literature; (2) conduct an online Delphi survey and (3) consensus meeting of stakeholders including trials researchers, knowledge users, research funders, journal editors, and PPI (patient and public involvement) representatives; (4) produce and disseminating extension checklists and associated explanatory documents.
We aim to complete the scoping review by end of 2020, prior to commencing funding for this study. The output from the review will be a list of items (approximately 40) related to reporting design, conduct and analysis of factorial trials. Phase 2 of the study is an online Delphi survey. Participants will rate importance of each item on the provisional list for inclusion in guidance statements. We anticipate inviting around 100-130 participants. We will conduct two survey rounds. In round 2, participants will see their own round 1 responses and a summary of all other participants' responses. Following completion of round 2, items will be categorised as 'consensus in', 'consensus out' or 'no consensus'.
'Consensus out' items will be discarded and all other items taken forward to a consensus meeting of around 30 participants. Each item will be presented and voted on for inclusion in final checklists for SPIRIT and CONSORT extensions for factorial trials.
We will produce and disseminate the extensions and supporting materials widely through publication, presentation at conferences and workshops, and free availability on the Equator Network and CONSORT and SPIRIT websites.
Publications
Kahan B
(2023)
Reporting of Factorial Randomized Trials Extension of the CONSORT 2010 Statement
in JAMA
Kahan B
(2023)
Consensus Statement for Protocols of Factorial Randomized Trials Extension of the SPIRIT 2013 Statement
in JAMA Network Open