Chohort definition: What is the difference between the first time of history and first_occurrence per person

[gyeol99 (Gyeol Song)]

Hi @pandamiao,

Although @SCYou’s explanation is pretty straightforward, I recommend you check out this topic as well.

First Exposure attribute vs earliest event

@Chris_Knoll and Atlas builders: What’s the difference between the two? I can choose First Exposure in History as a Criteria attribute, or I can select from the pop-down below the Initial Event Cohort definition by clicking on “earliest event”. Is there a difference?