analysplan

An analysplan is a document that specifies the planned statistical analyses for a study. It accompanies the study protocol and outlines how data will be processed, analyzed, and reported. Its primary purpose is to reduce bias by predefining analyses and to improve transparency and reproducibility.

A typical analysplan covers study objectives and predefined hypotheses; data sources, inclusion criteria, and variable definitions; data cleaning and handling of missing data; the statistical methods for primary and secondary analyses; plans for subgroup, interaction, and sensitivity analyses; and approaches to multiplicity, reporting, and software.

Analysplaner are common in clinical trials, epidemiology, and other quantitative research. They may be part of the protocol or a separate statistical analysis plan (SAP). Developing the plan before data access promotes preregistration, minimizes analytic flexibility, and supports peer review and regulatory scrutiny.

In qualitative research, a related document may describe analytic strategies such as coding and thematic analysis, but qualitative plans are usually less prespecified than quantitative ones.

Changes to an analysplan should be justified and documented if study conditions change, but the core plan should remain concise, actionable, and aligned with ethical considerations.