3.1.11 Cohort overlap

[ginberg]

From the SRS:

A series of tables or graphs showing the overlap between two cohorts.

The stacked bar shows the overlap in terms of subjects. It shows the number of subjects that belong to each cohort and to both. The diagram does not consider whether the subjects were in the different cohorts at the same time.

The table show the same information and more:

Subject in either cohort: The number of subjects that enter one or both cohorts. (The union)

Subject in both cohorts: The number of subjects that enter both cohorts, although not necessarily at the same time. (The intersection)

Subject in target not in comparator: The number of subjects that enter the target cohort, but not the comparator cohort. (Subtracting the comparator from the target)

Subject in comparator not in target: The number of subjects that enter the comparator cohort, but not the target cohort. (Subtracting the comparator from the target)

Subject in target before comparator: The number of subjects that enter both cohorts, but enter the target cohort before entering the comparator cohort. This number considers only the first entry per cohort per person.

Subject in comparator before target: The number of subjects that enter both cohorts, but enter the comparator cohort before entering the target cohort. This number considers only the first entry per cohort per person.

Subject in target and comparator on same day: The number of subjects that enter both cohorts on the same date. This number considers only the first entry per cohort per person.

Subject having target start during comparator: The number of subjects that enter the target cohort during the comparator cohort, meaning comparator cohort start date <= target cohort start date <= comparator cohort end date. This number considers only the first entry per cohort per person.

Subject having comparator start during target: The number of subjects that enter the comparator cohort during the target cohort, meaning target cohort start date <= comparator cohort start date <= target cohort end date. This number considers only the first entry per cohort per person.