Abstract
Objectives
To provide GRADE guidance on how to prepare Summary of Findings tables and Evidence
Profiles for time-to-event outcomes with a focus on the calculation of the corresponding
absolute effect estimates.
Study Design and Setting
This guidance was justified by a research project identifying frequent errors and
limitations in the presentation of time-to-event outcomes in the Summary of Findings
tables. We developed this guidance through an iterative process that included membership
consultation, feedback, presentation, and discussion at meetings of the GRADE Working
Group.
Results
Review authors need to carefully consider the definition of the outcome of interest;
although often the event is used as label for the outcome of interest (e.g., death
or mortality), the event-free survival (e.g., overall survival) is reported throughout
individual studies. Review authors should calculate the absolute effect correctly,
either for the event or absence of the event. We also provide examples on how to calculate
the absolute effects for events and the absence of events for various baseline or
control group risks and time points.
Conclusions
This article aids in the development of Summary of Findings tables and Evidence Profiles,
including time-to-event outcomes, and addresses the most common scenarios when calculating
absolute effects in order to provide an accurate interpretation.
Keywords
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Article info
Publication history
Published online: November 08, 2019
Accepted:
October 10,
2019
Identification
Copyright
© 2019 Elsevier Inc. All rights reserved.
