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The ‘Contains’ formula is a TRUE/FALSE statement used to check if a particular option was selected in a checkbox question type. In CMS (platform v1), the way to do that is to write something like this: [checkboxq(value)] == 1. This has been changed up in V2. The new formula to check if a checkbox contains a specific value is:

Contains([questionName], 2)

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• Contains([CheckboxQ1], 3)
  The formula will get the last response(s) for the question “CheckboxQ1” and check if '3' was ‘3' was one of them. If ‘3’ was one of them the logic will return TRUE and if '3’ was not one of them the logic will return FALSE.

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