A
cohort is a group of participants who share particular demographic or study characteristics (e.g., all the participants of one gender, or all those with a particular HIV status). Cohorts can be either:
- Simple: Assignments are fixed throughout the study
- Advanced: Assignments can change over time depending on some study characteristic
Once an administrator has
set up your Study to include cohorts, you can view participants and filter data by cohort.
View Cohort Assignments
Example In the
interactive example demo study, the "Demographics" dataset has been used to assign participants to two cohorts that stay the same throughout the study. The following screenshot displays this dataset and the column used to sort participants into "Group 1: Acute HIV-1" or "Group 2: HIV-1 Negative."
Filter Data by Cohort
In the Demographics dataset shown above, the "Cohort" column is visible, so that data could be filtered directly from the column header. In addition, within a study, datasets which don't have this column can still be filtered by cohort using the
Groups menu,
Cohorts option:
The Physical Exam dataset in the interactive example shows how you can filter by cohort using the
Groups menu. Try it yourself here:
Changing Cohorts Over Time
If your administrator has
set up "Advanced" cohorts, cohorts can vary over time. If this is the case, your
Groups > Cohorts menu will contain additional options. You will be able to filter by cohort and select one of the following:
- Initial cohort. You will see all participants that began the study in the selected cohort.
- Current cohort. You will see all participants that currently belong to the selected cohort.
- Cohort as of data collection. You will see participants who belonged to the selected cohort at the time when the data or a specimen was obtained.
View Individual Participants by Cohort
You can step through per-participant details exclusively for a particular cohort.
- Display a dataset of interest.
- Filter it by the desired cohort using Groups > Cohorts.
- Click a participantID.
- You now see a per-participant details view for this member of the cohort. Click "Next Participant" or "Previous Participant" to step through participants who are included in this cohort.
The information in the interactive example study can display per-participant views by cohort in this way. Click the following links to see:
Customize Grid to Show Cohorts Column
Cohort membership can be displayed as an extra column in a datagrid by creating a custom grid.
- Display the dataset of interest.
- Select (Grid Views) > Customize Grid.
- In the left panel, expand the ParticipantID node by clicking the .
- Place a checkmark next to Cohort.
- In the Selected Fields panel, you can reorder the fields by dragging and dropping.
- Click Save and name your custom grid, or make it the default for the page.
- The new grid will display a Cohort column that lists the cohort assigned to each participant.
