If your Registered Report plan changes after data collection, you should document the deviation transparently in your final manuscript, explaining what changed and why.
Registered Reports are designed to prevent post-hoc rationalization by locking in your methodology before you see the data. However, research rarely goes exactly as planned, and journals that accept Registered Reports understand this reality. The key is maintaining transparency about any departures from your pre-registered plan.
Document All Deviations Clearly
When writing your Stage 2 manuscript, create a dedicated section (often labeled "Deviations from Registered Plan") that explicitly lists what changed. For each deviation, provide:
- What changed: The specific aspect of your original plan that was modified
- Why it changed: The justification (e.g., technical failure, unforeseen data quality issues, participant recruitment challenges)
- When you decided: Whether the change was made before or after seeing outcome data
Distinguish Between Planned and Unplanned Analyses
Clearly separate your pre-registered confirmatory analyses from any exploratory analyses you conducted after seeing the data. Label exploratory findings as such—they're valuable for generating future hypotheses but shouldn't be presented as if they were predicted in advance.
Common Acceptable Changes
Most journals accept deviations when they're unavoidable, such as:
- Sample size falling short of your target despite documented recruitment efforts
- Equipment malfunction requiring alternative measurement approaches
- Discovering data quality issues that necessitate different exclusion criteria
- Statistical assumptions being violated, requiring different analytical approaches
What's Generally Not Acceptable
Changes that undermine the pre-registration's purpose are problematic:
- Switching your primary outcome measure after seeing results
- Adding new hypotheses based on observed patterns
- Changing exclusion criteria to achieve desired results
Editors evaluate Stage 2 submissions based on whether you followed your approved protocol in good faith and reported honestly when circumstances forced changes. Transparency protects your credibility and maintains the Registered Report format's integrity. Transparency protects your credibility and maintains the Registered Report format's integrity.
