You can pass custom identifiers—like participant IDs, tags, or tokens—through your Optimal study to track and reconnect participant data across systems.
This is especially useful when you're inviting participants via panel providers, CRM systems, or internal platforms where you need to preserve identifiers in redirect URLs.
What are parameters and why use them?
A parameter is a piece of information appended to a URL, like:
In studies, these parameters are used to:
Track who completed the study (e.g.
token=12345)Segment participants (e.g.
tag=marketing)Chain studies: Carry a participant identifier through multiple studies without asking them to enter their details multiple times (e.g.
entry=xyz)
Supported parameters
There are 3 predefined types of redirect parameters:
Type | Incoming Example | Placeholder in Redirect URL | Description |
|
|
| Unique participant ID (primary). Useful for chaining studies. |
|
|
| Secondary identifier |
|
|
| Segmentation tag (e.g. department) |
You can also pass fixed parameters if you'd like to always include static values in your redirect URLs.
Redirect the parameters out of your study
There are three places to add a Redirect URL in an Optimal study:
1. Complete Redirect URL
Participants are redirected here when they complete your study.
Located under the Study Flow tab under Setup, under the Thank you message section.
2. Closed Redirect URL
Participants are redirected here if your study has closed.
Located under the Study Flow tab under Setup, under the Closed message section.
3. Rejection Redirect URL
Participants are redirected here if they are rejected by one of your screening question.
Located under the Study Flow tab under Setup, under Screening questions (if you have set up screening questions).
Integrate with external recruitment panels
Our redirect URL assistant is here to help you integrate with external recruitment providers:
When configuring redirects in Optimal, our assistant helps guide parameter setup:
Detects your redirect URL and extracts all query parameters
Asks you to classify each parameter as either:
entry,token,tagOr mark it as a fixed/static value
3. Builds two example URLs:
The incoming study URL with dynamic placeholders
The final redirect URL that includes actual values or tokens
These examples help validate your setup before launching.
Testing your setup
Use the Preview feature after setup to validate:
The correct parameter types are used
The incoming and redirect URLs look as expected
If any issues appear, return to the assistant and revise inputs.
Advanced usage: Manual URL editing
If you're managing redirects manually, here are some tips:
To manually build a redirect with fixed values and tokens:
<https://yourplatform.com/complete?panel=acme&rid=[ENTRY]&seg=[TAG]>
Ensure you use supported placeholders:
[ENTRY],[TOKEN],[TAG]Do not URL-encode square brackets (
[])
Need help?
Still unsure how to configure your parameters? Contact our support team — we’re happy to assist.
Need some more help recruiting participants?
Struggling to set up your study with an external recruitment provider? We can help.
We offer participant recruitment services that will help you find participants quickly and easily, and we'll handle the query parameter token and redirect URLs for you.