Data and analysis populations
Finalize data and derive populations
Analysis populations can overlap. Define assignment-based, safety and per-protocol populations without treating them as disjoint partitions. Excluding nonadherent participants can introduce selection and does not by itself estimate a causal per-protocol effect.
Flow diagram
Steps
Review data quality and queries
Reconcile source data and document adjudication.
Review deviations before unblinding
Prespecify handling and decision authority.
Derive endpoints and covariates
Version all transformations and analysis programs.
Specify analysis populations
Define assignment-based, safety and per-protocol populations with explicit rules. These populations may overlap. Excluding nonadherent participants alone does not identify a causal per-protocol effect.
Finalize and release datasets
Document locking, authorized access and retained versions.
Data and analysis populations
End flow
Tables and supporting information
Analysis population definitions
Overlapping populations are not an arithmetic partition.
Dataset lineage
Keep analysis inputs reproducible.