ID Deduplication

Updated
  • Updated on May 7, 2025
  • Published on Apr 1, 2025
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ID Deduplication prevents multiple entries from the same participant ID, making sure that each respondent can take the survey only once under a unique identifier. You can now enable or disable this check per project with a single toggle in

Project → Security → ID Deduplication.

Key Benefits

Guaranteed Participant Uniqueness
When enabled, each participant can only enter once by using a unique ID.

Reliable Panel Management
Ideal for studies that use panel providers assigning consistent respondent IDs.

Flexible Configuration
Toggle the check on or off without redeploying links, giving you control when working with trusted suppliers or internal audiences.

How It Works

  1. Toggle the setting on or off in the Security section of your project settings.

  2. When enabled, every participant must pass a unique ID into dtect as part of the entry request.

  3. If the incoming ID has already been statused for that study, the respondent is blocked automatically and flagged with Security Terminate status.

  4. When disabled, dtect accepts all respondents regardless of ID duplication.

Configurable ID Deduplication

Enable the check if you need hard guarantees that each respondent appears only once. Disable it for pilots, internal tests, or trusted closed loops where participant identity is controlled outside of dtect.

When to Enable

Turn the switch on when working with:

  • Panel‑based research that relies on stable respondent IDs

  • Loyalty programs or communities using known customer identifiers

  • High‑value studies where identity integrity is critical

When to Disable

Consider leaving the switch off when:

  • Recontacting / Re-inviting participants

  • Running ad‑hoc QA or link tests

  • Collecting feedback from internal teammates who may reuse accounts

  • Piloting studies with sandbox or staging environments

Best Practices

1. Confirm Supplier Compliance
Ask suppliers to pass a unique, stable ID for every participant whenever the check is enabled.

2. Avoid Temporary or Recycled IDs
Dynamic identifiers can cause false positives or data loss. Work with suppliers to ensure stability.

3. Monitor Entry Logs
Use the Progress page export to spot patterns such as repeated failed attempts on identical IDs. This often points to intentional manipulation.

Troubleshooting

Missing IDs
If participants fail entry with the check enabled, confirm that the supplier passes the id parameter in the redirect URL or entry script.

Unexpected Terminations
Some systems reuse IDs across studies, this is fine. Make sure identifiers are unique at the study level or disable the check when reuse is unavoidable.

💡 Pro Tip

You can toggle ID Deduplication at any time, even after launching a project. Changes apply instantly, allowing quick mitigation if false positives appear or stricter controls become necessary.