Understand how subject number assignment impacts a study

Learn how the timing of subject number assignment - whether during subject addition or after submitting screening forms - affects study data, data propagation to downstream applications, and overall system behavior.

When a subject number is assigned depends on the study configuration and user actions. For more information, see Specify study settings and Workflow to configure subject number assignment after screening.

The following table provides different use cases and their impact on study data.

Subject numbers are assigned upon addition	Subject numbers are assigned upon screening
Enrollment limits validation The system checks enrollment or screening limits after data entry, upon selecting Screen when adding a subject: If limits are reached, the system prevents the screening and shows an error message. However, as the subject number is already assigned, any data that was collected and saved during the screening visit remains. If within limits, the system allows the screening of the subject. Subject number is already assigned (whether manually or automatically), regardless of the screening event.	Enrollment limits validation The system checks Study, Country, and Site enrollment limits in real time: If limits are reached, users are prevented from starting the screening candidate process . In these cases, the Screen Candidate button is disabled, avoiding data entry for a subject that won't be screened due to closed enrollment. Subject data is never entered, subject is not screened and subject number is not assigned. If within limits, the process to screen a candidate can be started and data can be entered. If the subject is screened (either successfully or not) the study assigns a subject number. This can occur manually or automatically, depending on the study's settings. Other enrollment limits, such as those for cohorts and custom enrollment groups, are still validated but upon data submission only. This happens when selecting the Submit button: If the subject is screened (either successfully or not) data is submitted and subject number is assigned. If the screening doesn't proceed, data is not saved and subject number is not assigned.
Data save and propagation As soon as the subject is added to the study and data is entered for them, data on the subject is available in the applicable integrations, reports, Oracle CRF Submit archives, and Oracle Clinical One Analytics datasets. Even if site user collects data but cancels or leaves forms without submitting data, any data collected until then is automatically saved and preserved in the system.	Data save and propagation Only after the subject is screened (either successfully or not), subject data is available in reports, Oracle CRF Submit archives, Oracle Clinical One Analytics datasets, Oracle Central Coding and all applicable integrations. Note: If your study integrates with Oracle Central Coding and the Code data for new and screen failed subjects setting on the Study Settings tab is disabled, Oracle Central Coding data will not be sent until the subject is enrolled or randomized. EHR linking occurs later by selecting the appropriate option on the Manage drop-down.
Subject status Subjects may have a status of New, Screened, or Screen Failed: As soon as the subject is added, the subject is already assigned a number, so they remain visible on the Subjects page with a status of New. Only after the screening event is complete, the subject's status changes to Screened or Screen Failed.	Subject status Subjects get a status of either Screened or Screen Failed: The system doesn't assign a subject number if the site user cancels, doesn't submit, or leaves the screening form. No new subject appears on the Subjects page and data is not saved. Note: The system shows a warning to prevent accidental data loss. The subject's status changes to Screened or Screen Failed only after the screening forms are submitted. Site users cannot manually screen fail a subject until the subject has been screened.
Queries and rules Queries and rules function normally on added subjects, given that they are already available on the Subjects page.	Queries and rules Manual queries, automated queries, notifications, and other custom JavaScript rules cannot be raised for a subject until a subject number is assigned.