Writing & StyleStyle guide

Examination of Subgroups in Clinical Study Report

ICH E3 section 11.4.2.8 calls for relevant subgroup examinations to be described and interpreted with appropriate caution. Subgroup examination should not be presented as though every subgroup comparison were confirmatory; interpretation depends on planning, multiplicity, sample size, and study context.

Quick answer

Identify prespecified or otherwise relevant subgroups, present the analyses transparently, and distinguish supportive or exploratory findings from the primary efficacy conclusion.

Key details

Core IssueICH E3 section 11.4.2.8 calls for relevant subgroup examinations to be described and interpreted with appropriate caution.
Registerscholarly, professional, or research/report writing

Important caveats

Scope Boundary

Subgroup examination should not be presented as though every subgroup comparison were confirmatory; interpretation depends on planning, multiplicity, sample size, and study context.

Further guidance

Content

Identify prespecified or otherwise relevant subgroups, present the analyses transparently, and distinguish supportive or exploratory findings from the primary efficacy conclusion.

Purpose

Identify prespecified or otherwise relevant subgroups, present the analyses transparently, and distinguish supportive or exploratory findings from the primary efficacy conclusion.

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.

  1. E3 Structure and Content of Clinical Study Reports (opens in a new tab)U.S. Food and Drug Administration · FDA-hosted ICH E3 guidance defining the structure and content of a core clinical study report

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