Tutorial 15 · Advanced logic
URL variables and random groups
Personalize a survey from a declared link parameter and assign each respondent to a stable experiment group.
1. Prepare the survey
Open a practice survey from Home and click Edit. Add these pages and questions in the order shown. Click a question type in the builder palette, then select the question to edit its label and choices. Use Add Page for later pages.
| Page | Question | Type and setup |
|---|---|---|
| Personalized session | Campaign: general · Group: unassigned | Text box · Optional initially |
Follow along in a practice survey in the VividSurvey app. Screenshots illustrate each step.
2. Configure the logic
Declare the campaign
Choose URL variables and random groups. Click Add variable. Set URL parameter to campaign, Type to Text, and Default to general.
Add random assignment
Click Add variable again. Set URL parameter to experiment, Type to Random group, and Group names, separated by commas to Group A,Group B. These names are case-sensitive values you can use in conditions.
Review and save variables
Click Next, inspect both declarations, and Save logic.
Use the values in text
Use Insert a previous answer to insert campaign into Question text with Text before the answer set to Campaign: and a space, and fallback general. Use the same wizard again to insert experiment into that question’s Description, with prefix Group: and fallback unassigned. The supplied review example shows both values in one label.
Open a campaign link
Publish. Add ?campaign=spring to the public survey URL before first opening the respondent session. The app assigns the experiment group; it is not selected by the campaign parameter.
3. Review the logic flow
Read the final flow before saving. For conditional rules, YES means the condition matches and NO means it does not. An unanswered source can leave the rule waiting. Use Try answers when it is available, or Back to adjust the setup. View full survey flow provides the surrounding page order and saved rules.
4. Save and publish
Save the reviewed logic
On the final wizard step, click Save logic. Your changes join the survey draft. If the tutorial creates more than one rule or setting, complete and save every part before publishing.
Confirm the draft is saved
Close Logic. Wait for the builder’s save/sync status to complete. You can reopen Logic to check the saved rule or setting. Save logic does not by itself update the public survey.
Publish the survey
Click Publish in the builder, then Publish Now in the confirmation. Use the public link to test the published survey. After later edits, publish again before checking the live result.
Test in a fresh respondent tab
Start with a fresh public survey tab. If you already had an older published version open, reload and start a new response. Use a practice survey for test submissions.
5. Test the respondent experience
Run both the matching and alternative cases. Change answers and revisit earlier pages where the test asks you to, rather than testing only one path.
| Try this | Expected result |
|---|---|
| Open a fresh ?campaign=spring link | Campaign reads spring and a Group A or Group B value is displayed. |
| Reload that respondent session | The campaign and random assignment stay fixed. |
| Use a fresh session without campaign | The declared default general is used. |
Common mistakes and useful limits
- URL values are public input, not proof of identity or permission.
- Change link parameters before starting a new respondent session; an existing session retains its captured values.