Hi all
I am interested in creating a choice list for a select_one question that is based on the participants' responses to 8 separate yes/no questions.
First they are asked whether they used product A, product B, product C... selecting yes or no to each (we deliberately do not have this as a select multiple question as in piloting, participants weren't considering the entire list).
Then we would like to know the main product they used. I would like the choices to be only those that they responded "yes" to previously.
Is there a way to do this with choice_filter? Any ideas or advice would be appreciated!
Thank you
Welcome on the ODK Community forum @kateanelson !
We're glad you're here. When you get a chance please take the time to introduce yourself in the dedicated topic 
You can achieve what you want to do with a appropriate choice_filter clause.
Here is an example :
Choice_filter_based_on_select_one_questions.xlsx (9,3 Ko)
The calculate (line 9) concatenates the products names selected in previous select_one questions.
In the choice_filter of the select_multiple question you just need to check whether the "used_products" variable contains the current option name.
Another option : the rank question type may be relevant for your need ?
Thank you for the welcome & quick input! This is very helpful