Data Collection Strategies for Repeating Surveys
Collect recurring survey data in REDCap using repeating instruments, repeating events, Automated Survey Invitations, Alerts & Notifications, and the Survey Queue.
This guide will help you choose the right setup for your study and avoid common configuration issues.
Core Concept: One Record → Multiple Survey Instances → Repeated Data Over Time
On this page
Overview
Repeating surveys allow participants to complete the same survey multiple times, with each submission stored as a separate instance.
- Repeating Instruments: One form repeats multiple times
- Repeating Events: Entire visit/event repeats (longitudinal only)
Important: These methods can be combined. Choose based on workflow—not technical preference.
Comparison of Methods
| Method | Best For | Email Required? |
|---|---|---|
| Repeat Survey Button | Multiple entries in one sitting | No |
| Automated Invitations (ASI) | Scheduled recurring surveys | Yes (or SMS/voice) |
| Alerts & Notifications | Conditional workflows | Yes |
| Survey Queue | Participant-driven access | No |
Best practice: The most common setup is Repeating Instrument + Automated Survey Invitations.
Decision Guide
Ask yourself:
- Do participants complete surveys on a schedule? → Use ASI
- Do surveys depend on conditions? → Use Alerts
- Do participants return anytime? → Use Survey Queue
- Do they enter multiple entries at once? → Repeat Survey Button
Repeating Instruments vs Events
| Feature | Repeating Instrument | Repeating Event |
|---|---|---|
| What repeats | Single survey | Entire visit |
| Complexity | Simple | More complex |
Recommendation: Use repeating instruments whenever possible.
Survey Queue
The Survey Queue provides a central page where participants can access available surveys.
Best practice: Use for long-running studies where participants return regularly.
Example Configurations
- Daily Survey: Repeating Instrument + ASI
- Medication Log: Repeating Instrument + Repeat Button
- Conditional Follow-Up: Alerts + [new-instance]
- Clinical Visits: Repeating Event
How Instances Work
Participant completes survey → Instance #1
Completes again → Instance #2
Completes again → Instance #3
Think of each instance as a new row of data tied to the same participant.
Testing
- Create test records
- Submit multiple instances
- Verify invitations
- Confirm new instances are created
- Test participant experience
Best practice: Test the full workflow—not just the survey.
Exporting Data
- Each instance = one row
- Include repeat instance fields
- Long format is typically preferred
Troubleshooting
- Same instance opens: Missing
[new-instance] - Too many emails: Check ASI timing
- No new rows: Repeating not enabled
- No repeat button: Not enabled in settings
Common issue: Using repeating events when a repeating instrument would be simpler.
Configuration Checklist
- Choose repeating type
- Enable repeating
- Select delivery method
- Configure logic/timing
- Use [new-instance] if needed
- Test thoroughly
- Validate export structure