Have you ever started a survey, only to be told part-way through that you're not eligible to complete it? This can be a frustrating experience. You might feel like your time has been wasted or that your opinions don't matter. But there's actually a good reason for this. It's all about something called the 'screening process'. In the world of market research, the screening process is an essential step in ensuring the validity of survey results. This article provides a simple, in-depth explanation of how screening works and why you might sometimes be screened out of a survey.