is a group of participants who share a particular demographic or study characteristic (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, such as disease progression or treatment response.
Once an administrator has set up your Study to include cohorts
, you can view participants and filter data by cohort.
Cohorts are similar to participant groups
, but have a some additional built in behavior. You can only have one set of cohorts in a study, but multiple kinds of participant groups as needed. An administrator must define and manage study cohorts
; editors can add participant groups.
View Cohort Assignments
Within a dataset, you can see cohort assignments in a grid that includes the Cohort
column. For example, in the interactive example demo study
, the "Demographics" dataset shows which cohort each participant is in: "Group 1: Acute HIV-1" or "Group 2: HIV-1 Negative".
If you don't see this column, you can add it to a study dataset following the steps listed below
Filter Data by Cohort
When the "Cohort" column is shown in the grid, the dataset can be filtered directly from the column header. In addition, study datasets which don't show this column can still be filtered by cohort using the Groups
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
, cohort assignments 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: All participants that began the study in the selected cohort.
- Current cohort: All participants that currently belong to the selected cohort.
- Cohort as of data collection: Participants who belonged to the selected cohort at the time when the data or a sample 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
To add the "Cohort" column in a data grid:
- Display the dataset of interest.
- Select (Grid Views) > Customize Grid.
- In the left panel, expand the ParticipantID node by clicking the .
- Check the box for 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.