# Preregistration and analysis plan

Adapt these templates to your discipline, institutional rules and actual project.

## Questions and hypotheses

State question, estimand and relevant hypotheses; disclose prior data knowledge.

Actual decision, rationale and evidence location: ____________________

## Outcomes and sample

Operationalize primary outcome, units, timing, population, sampling and eligibility.

Actual decision, rationale and evidence location: ____________________

## Sample size and stopping

Justify power/precision inputs, attrition and stopping before results.

Actual decision, rationale and evidence location: ____________________

## Exclusions and missingness

Specify exclusion, missingness and outlier rules with assumptions.

Actual decision, rationale and evidence location: ____________________

## Models and exploratory work

Record model, adjustment, multiplicity, sensitivity and exploratory boundaries.

Actual decision, rationale and evidence location: ____________________

## Version and change rationale

Date changes, data already seen, reasons and consequences; preserve the old plan.

Actual decision, rationale and evidence location: ____________________

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## Related example and decision record

Decision workbook and teaching example · 2026-10-06

The completed case is fictional. Its values and decisions are not actual findings; complete your project using relevant permissions, methods and requirements.

- Project: ____________________
- Researcher and role: ____________________
- Date and version: ____________________
- Data seen before the decision: ____________________
- Aim and scope: ____________________

## Completed example

| Stage/decision | Example | Check or action |
| --- | --- | --- |
| Question | Defined association, not desired result | Are hypothesis and units clear? |
| Prior access | Which data/outputs were seen? | Is this disclosed before registration? |
| Plan | Outcome, exclusions, missingness and model | Are ambiguous choices reduced? |
| Amendment | Change after a new variable is seen | Are date, reason and consequence recorded? |
| Report | Planned and exploratory separated | Does it match registration history? |

## Complete your own record

| Topic | Actual decision and reason | Evidence link and status |
| --- | --- | --- |
| Question | __________ | __________ |
| Prior access | __________ | __________ |
| Plan | __________ | __________ |
| Amendment | __________ | __________ |
| Report | __________ | __________ |

## Completion checks

- [ ] Prepare an assessable plan, prior-access disclosure and deviation log.

## Changes and limitations

| Date | Change | Data known at decision time | Reason | Consequence for claim | Reviewer |
| --- | --- | --- | --- | --- | --- |
| __________ | __________ | __________ | __________ | __________ | __________ |

## Sources and further reading

- [Center for Open Science — Preregistration](https://www.cos.io/initiatives/prereg)
- [PRISMA 2020 — Statement and checklists](https://www.prisma-statement.org/prisma-2020)
- [MIT Libraries — Write a data management plan](https://libraries.mit.edu/data-management/plan/write/)

Related guide: https://didgar-research-site1.vercel.app/en/guides/preregistration/