Analysis Population Section
SPIRIT 2025 item 27b calls for protocols to define who will be included in each analysis and in which group, including clear definitions for the primary and any additional analysis populations. This is distinct from a Study Population section, which describes the population being studied, and from the statistical-methods content that explains how outcomes will be analyzed.
An Analysis Population section defines which participants or observations are included in each planned analysis and how they are grouped.
Key details
Important caveats
Scope Boundary
This is distinct from a Study Population section, which describes the population being studied, and from the statistical-methods content that explains how outcomes will be analyzed.
Further guidance
Content
Define the primary analysis population and any additional populations, state inclusion/exclusion rules, specify which randomized or treated group participants are analyzed in, and avoid labels such as “modified intention-to-treat” unless fully defined.
Purpose
Make the denominator and grouping rules for each planned analysis explicit before results are known.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- SPIRIT 2025 explanation and elaboration: updated guideline for protocols of randomised trials (opens in a new tab)BMJ / SPIRIT-CONSORT Group · Primary SPIRIT 2025 explanation and elaboration for trial protocols, including trial monitoring and data monitoring committee roles and reporting structure.