How to stop a questionnaire based on an answer (Screenout).

Objective

• Understand the screenout mechanism in LimeSurvey.
• Configure a quota to terminate a questionnaire based on a response.
• Customize the end message displayed to excluded participants.

Why use quotas for screenouts?

• To properly terminate the questionnaire as soon as an exclusion criterion is met.
• To display a customized message to ineligible participants.
• To avoid errors related to complex conditions that simply hide questions.

1. Preparing the questions

Before configuring the quota, ensure your screening question is properly set up.

1. Verify that your question is of type "List (Radio buttons)" or "Yes/No".
2. Note the response code that should trigger the termination (for example 0 for "No" or A2 for a specific option).

Note: The response code can be found in the question editor, in the "Code" column of each response option.

2. Creating the quota

1. Go to the "Settings" tab of your questionnaire.
2. In the side menu, click on "Quotas".
3. Click the "+ Add new quota" button.
4. Fill in the following fields:
   • Quota name: Give an explicit name (example: Failed_Consent).
   • Quota limit: Enter 0. This means that as soon as a person matches the criterion, they exceed the allowed limit.
   • Quota action: Select "Terminate survey".
   • Quota message: Write the message the participant will see (example: "Thank you for your interest, but your profile does not match the criteria for this study.").
5. Click "Save".

3. Linking the question to the quota

Once the quota is created, it is "empty". You must specify which response to monitor.

1. In the quota list, locate the one you just created.
2. Click the "Add answer" button (often represented by a + icon).
3. In the window that opens, select the relevant Question.
4. Check the Response that should trigger the termination (example: "No").
5. Click "Save".

Tip: If your questionnaire has multiple versions of the same question (for example a consent question for minors and one for adults), create a separate quota for each question.

4. Testing and activation

Quotas only become active when the questionnaire is activated.

1. Activate the questionnaire.
2. Perform a real test by responding with the exclusion value.
3. Verify that you are properly redirected to the customized end message.

Common error: If the questionnaire blocks for all participants without apparent reason, check that no contradictory condition was left in the "Conditional filter equation" field of the following groups.

5. Quotas vs Conditions: comparison

Here are the key differences between the two methods:

Quotas

• Usage: Exclude or stop a participant.
• Complexity: Very simple, no code required.
• Message: Customizable end message.
• Reliability: Very high.

Conditions (ExpressionScript)

• Usage: Hide or show questions.
• Complexity: Requires logical formulas.
• Message: Simply redirects to the standard end.
• Reliability: Risk of errors if questions are hidden.

Note: Always prefer quotas for screenouts. Conditions should be reserved for conditional display of questions.

6. Typical use cases

Consent refusal

The participant answers "No" to the consent question. The quota with limit 0 immediately terminates the questionnaire with a thank you message.

Age criterion not met

The participant indicates an age below 18 years. A quota linked to this response stops the questionnaire and displays a message explaining that the study is reserved for adults.

Multiple screening branches

If your questionnaire includes randomization or multiple filters, create a quota for each screening question. LimeSurvey will automatically check which quota applies based on the participant's path.

Need help?

For any difficulty, contact the LimeSurvey team via: Cellule.Web@ulb.be