Table 2. Needs for specified capabilities in implementing patient lists.

The set of patients in a list can originate from an internal IDR query or from an external source such as a study or clinical database.

	Origin of list
Functional capability	Internal query	External source
1. Feedback from Internal Query:  Feed patient IDs from a query result back to the IDR	needed	not needed
2. Permanent Identifier:  Exposability of a permanent ID in the IDR	needed	needed
3. Adding Attributes to IDR:  Allow adding queryable attributes to IDR	needed	needed
4. Convert External ID:  Ability to convert external ID to IDR’s standard ID	not needed	needed
5. Merge Multiple Queries:  Merge multiple accessions of a list on common identifiers	needed	needed
6. Modifying List Membership:  Allow modification of list membership over time	less likely	more likely
7. Policies on De-identification:  Implement policies on levels of de-identification on data returned from list-based query.	needed	needed
8. Restricted Use:  Ability to restrict use of a list to authorized persons	needed	needed
9. Avoid Inadvertent Exposure:  Use of a list in a query must not inadvertently expose unauthorized data.	needed	needed