I'm developing an app that asks users to fill in a questionnaire which consists of multiple screens. Each screen includes the question text, a graphic, and Yes/No buttons that are always in the same spot. What we've noticed is that some users touch the screen multiple times and so inadvertently record "Yes" for a screen without having read it.

To prevent this we've implemented a delay so that clicks are ignored if they happen within 2 seconds of the page being shown. However this can leave some people who don't want to read the question (e.g. testers & trial users) confused about what the program is doing. Does anyone have an idea on how to indicate that the click was ignored due to such a delay?

I'd like to avoid requiring two clicks (i.e. first on a "Yes" then on a "Go to next question").

Thanks!