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Your LimeSurvey version: Basic

Theme: Survey design/conditions - end page code for external website
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Hello, I am setting up my survey and I would be using clickworker (service that finds and pays respondents) to gain survey participants quickly. When a respondent completes my survey, they will receive a verification code on the end page (code can be the same for all).However, I have a quota for a screening test. The respondents who are filtered out by the quota should not receive a code on their end page. Could you please help me with an easy solution to this. I am not a programer so the coding intimidates me.

thanks in advance! 

You need to use quota to screen people out. In the quota you can define how many people you want to allow for each quota (e.g. 50 men, 50 women). In your case, you want to screen them out, so you need to use what we call a "zero quota". So the number of acceptable respondents with the specific characteristics you want to screen them out for is zero. For each quota, you can define a specific message. People how ran into a completed quota will not make it to the end message, but will just see the specific quota message.

When you play around with quota, please keep in mind that they only work when the survey is active (in the test mode nothing is stored in the database, so the quota will never close).

Thank you very much! this really helps. i wasn't sure if respondents who are screened out with a quota get the same end message as others

No, they don't. And they also don't count into completed interviews.

Just set up a quota for test purposes. You can define a specific message per quota and you can also define a end-url/redirect per quota.

E.g. you can tell them: You are too young. Or "You are male, this survey is only for women", etc.