lock

The lock tag prevents changes to a variable after selection.

PATH. Survey Path
type: coded single select
lock: y
1. Path A {if anyChecked($Q2,1)}
2. Path B {if anyChecked($Q2,2)}

Variables and quotas are "unlocked" by default, allowing variables to be re-punched if a respondent uses navigation buttons to go backwards and change their responses. This behavior is helpful for testing but should be disabled during live surveys to maintain data integrity. Add lock: y to key variables like routing questions and quotas to preserve critical survey logic.