Please help us help you and fill where relevant:
LimeSurvey version: LimeSurvey Community Edition Verze 6.5.8+240517
Own server or LimeSurvey Cloud: Our own server
Survey theme/template: one of the basics
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Hi there, 

following one of the tips from here, we added a hidden question to our multilingual survey to later be able to use logic by the language of survey the user have selected. It was equation type question with aswer of (LANG) and it worked. 
Now that the survey is running and the results are filling in, we would like to monitor the answers. The inbuilt statistics are the best way to do it, but the hidden question of language isnt there fo filter by. Looking at the answers though, the column is filled by tle Lang chosen. 

Any idea how to filter by this hidden equation type question? 

Thank you. 
Lukas
 

Hi,
as you saw you can't filter by equations. And in your case the content is of type "text".
You should have created a (hidden) list(radio) and assigned the result of your equation, like
​​​​{Qlang=if(LANG=='en',1,if(LANG=='fr',2,if(LANG==...)))}

or similar.

Now you can filter by Qlang.

Joffm