Translations:Check survey logic - Advanced/204/en
From LimeSurvey Manual
You may also note that certain questions are displayed only if the answer to the previous question is not empty. You may see below that if p2_sex is not filled in, p2_name is not going to be displayed, even though it is a mandatory questions. The mandatory question p2_age is also not going to be displayed if p2_name is not filled in. These questions can be considered "conditionally mandatory".